CN106873332A - Image forming apparatus - Google Patents
Image forming apparatus Download PDFInfo
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- CN106873332A CN106873332A CN201710105753.2A CN201710105753A CN106873332A CN 106873332 A CN106873332 A CN 106873332A CN 201710105753 A CN201710105753 A CN 201710105753A CN 106873332 A CN106873332 A CN 106873332A
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- intermediate transfer
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Classifications
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- G—PHYSICS
- G03—PHOTOGRAPHY; CINEMATOGRAPHY; ANALOGOUS TECHNIQUES USING WAVES OTHER THAN OPTICAL WAVES; ELECTROGRAPHY; HOLOGRAPHY
- G03G—ELECTROGRAPHY; ELECTROPHOTOGRAPHY; MAGNETOGRAPHY
- G03G13/00—Electrographic processes using a charge pattern
-
- G—PHYSICS
- G03—PHOTOGRAPHY; CINEMATOGRAPHY; ANALOGOUS TECHNIQUES USING WAVES OTHER THAN OPTICAL WAVES; ELECTROGRAPHY; HOLOGRAPHY
- G03G—ELECTROGRAPHY; ELECTROPHOTOGRAPHY; MAGNETOGRAPHY
- G03G15/00—Apparatus for electrographic processes using a charge pattern
- G03G15/14—Apparatus for electrographic processes using a charge pattern for transferring a pattern to a second base
- G03G15/16—Apparatus for electrographic processes using a charge pattern for transferring a pattern to a second base of a toner pattern, e.g. a powder pattern, e.g. magnetic transfer
-
- G—PHYSICS
- G03—PHOTOGRAPHY; CINEMATOGRAPHY; ANALOGOUS TECHNIQUES USING WAVES OTHER THAN OPTICAL WAVES; ELECTROGRAPHY; HOLOGRAPHY
- G03G—ELECTROGRAPHY; ELECTROPHOTOGRAPHY; MAGNETOGRAPHY
- G03G15/00—Apparatus for electrographic processes using a charge pattern
- G03G15/14—Apparatus for electrographic processes using a charge pattern for transferring a pattern to a second base
- G03G15/16—Apparatus for electrographic processes using a charge pattern for transferring a pattern to a second base of a toner pattern, e.g. a powder pattern, e.g. magnetic transfer
- G03G15/1665—Apparatus for electrographic processes using a charge pattern for transferring a pattern to a second base of a toner pattern, e.g. a powder pattern, e.g. magnetic transfer by introducing the second base in the nip formed by the recording member and at least one transfer member, e.g. in combination with bias or heat
- G03G15/167—Apparatus for electrographic processes using a charge pattern for transferring a pattern to a second base of a toner pattern, e.g. a powder pattern, e.g. magnetic transfer by introducing the second base in the nip formed by the recording member and at least one transfer member, e.g. in combination with bias or heat at least one of the recording member or the transfer member being rotatable during the transfer
- G03G15/1675—Apparatus for electrographic processes using a charge pattern for transferring a pattern to a second base of a toner pattern, e.g. a powder pattern, e.g. magnetic transfer by introducing the second base in the nip formed by the recording member and at least one transfer member, e.g. in combination with bias or heat at least one of the recording member or the transfer member being rotatable during the transfer with means for controlling the bias applied in the transfer nip
-
- G—PHYSICS
- G03—PHOTOGRAPHY; CINEMATOGRAPHY; ANALOGOUS TECHNIQUES USING WAVES OTHER THAN OPTICAL WAVES; ELECTROGRAPHY; HOLOGRAPHY
- G03G—ELECTROGRAPHY; ELECTROPHOTOGRAPHY; MAGNETOGRAPHY
- G03G15/00—Apparatus for electrographic processes using a charge pattern
-
- G—PHYSICS
- G03—PHOTOGRAPHY; CINEMATOGRAPHY; ANALOGOUS TECHNIQUES USING WAVES OTHER THAN OPTICAL WAVES; ELECTROGRAPHY; HOLOGRAPHY
- G03G—ELECTROGRAPHY; ELECTROPHOTOGRAPHY; MAGNETOGRAPHY
- G03G15/00—Apparatus for electrographic processes using a charge pattern
- G03G15/14—Apparatus for electrographic processes using a charge pattern for transferring a pattern to a second base
- G03G15/16—Apparatus for electrographic processes using a charge pattern for transferring a pattern to a second base of a toner pattern, e.g. a powder pattern, e.g. magnetic transfer
- G03G15/1605—Apparatus for electrographic processes using a charge pattern for transferring a pattern to a second base of a toner pattern, e.g. a powder pattern, e.g. magnetic transfer using at least one intermediate support
-
- G—PHYSICS
- G03—PHOTOGRAPHY; CINEMATOGRAPHY; ANALOGOUS TECHNIQUES USING WAVES OTHER THAN OPTICAL WAVES; ELECTROGRAPHY; HOLOGRAPHY
- G03G—ELECTROGRAPHY; ELECTROPHOTOGRAPHY; MAGNETOGRAPHY
- G03G15/00—Apparatus for electrographic processes using a charge pattern
- G03G15/14—Apparatus for electrographic processes using a charge pattern for transferring a pattern to a second base
- G03G15/16—Apparatus for electrographic processes using a charge pattern for transferring a pattern to a second base of a toner pattern, e.g. a powder pattern, e.g. magnetic transfer
- G03G15/1605—Apparatus for electrographic processes using a charge pattern for transferring a pattern to a second base of a toner pattern, e.g. a powder pattern, e.g. magnetic transfer using at least one intermediate support
- G03G15/161—Apparatus for electrographic processes using a charge pattern for transferring a pattern to a second base of a toner pattern, e.g. a powder pattern, e.g. magnetic transfer using at least one intermediate support with means for handling the intermediate support, e.g. heating, cleaning, coating with a transfer agent
-
- G—PHYSICS
- G03—PHOTOGRAPHY; CINEMATOGRAPHY; ANALOGOUS TECHNIQUES USING WAVES OTHER THAN OPTICAL WAVES; ELECTROGRAPHY; HOLOGRAPHY
- G03G—ELECTROGRAPHY; ELECTROPHOTOGRAPHY; MAGNETOGRAPHY
- G03G15/00—Apparatus for electrographic processes using a charge pattern
- G03G15/14—Apparatus for electrographic processes using a charge pattern for transferring a pattern to a second base
- G03G15/16—Apparatus for electrographic processes using a charge pattern for transferring a pattern to a second base of a toner pattern, e.g. a powder pattern, e.g. magnetic transfer
- G03G15/1605—Apparatus for electrographic processes using a charge pattern for transferring a pattern to a second base of a toner pattern, e.g. a powder pattern, e.g. magnetic transfer using at least one intermediate support
- G03G15/1615—Apparatus for electrographic processes using a charge pattern for transferring a pattern to a second base of a toner pattern, e.g. a powder pattern, e.g. magnetic transfer using at least one intermediate support relating to the driving mechanism for the intermediate support, e.g. gears, couplings, belt tensioning
-
- G—PHYSICS
- G03—PHOTOGRAPHY; CINEMATOGRAPHY; ANALOGOUS TECHNIQUES USING WAVES OTHER THAN OPTICAL WAVES; ELECTROGRAPHY; HOLOGRAPHY
- G03G—ELECTROGRAPHY; ELECTROPHOTOGRAPHY; MAGNETOGRAPHY
- G03G15/00—Apparatus for electrographic processes using a charge pattern
- G03G15/14—Apparatus for electrographic processes using a charge pattern for transferring a pattern to a second base
- G03G15/16—Apparatus for electrographic processes using a charge pattern for transferring a pattern to a second base of a toner pattern, e.g. a powder pattern, e.g. magnetic transfer
- G03G15/1665—Apparatus for electrographic processes using a charge pattern for transferring a pattern to a second base of a toner pattern, e.g. a powder pattern, e.g. magnetic transfer by introducing the second base in the nip formed by the recording member and at least one transfer member, e.g. in combination with bias or heat
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- Physics & Mathematics (AREA)
- General Physics & Mathematics (AREA)
- Electrostatic Charge, Transfer And Separation In Electrography (AREA)
- Color Electrophotography (AREA)
- Control Or Security For Electrophotography (AREA)
Abstract
A kind of image forming apparatus, wherein, voltage maintains element to be connected to contact member, the contact member contacts the first transfer surface region transferred with the intermediate transfer belt of toner image from multiple images carrier between tension members, so as to the potential for preventing intermediate transfer belt changes between corresponding station.
Description
The application is the proposition of on March 29th, 2013, the application for a patent for invention of entitled " image forming apparatus "
The divisional application of No.201310105943.6.
Technical field
The present invention relates to a kind of electrophotographic image-forming apparatus, for example, duplicator or printer.
Background technology
Image forming apparatus including intermediate transfer member are traditionally known as electrophotographic image-forming apparatus.Traditional
Image forming apparatus include first voltage source (that is, power circuit), and the first voltage source can apply a voltage to first turning
Print component, the first transfer member is arranged in a face-to-face relationship with photosensitive drums via intermediate transfer member.Intermediate transfer member
Including first transfer section, photosensitive drums can be contacted in the first transfer section office intermediate transfer member.First transfer section
Potential maintain under predeterminated level (it is referred to as " transferring potential for the first time ").Then, traditional image forming apparatus are in photosensitive drums
First transfer process is performed in the state of formation predetermined potential is poor between intermediate transfer member, for will be formed in photosensitive drums
Toner image on the surface of (it is used as image-carrier) is transferred to intermediate transfer member for the first time.
Traditional image forming apparatus are repeatedly carried out above-mentioned first transfer process for each color in multiple color
To form multiple Color toner images on the surface of intermediate transfer member.Then, traditional image forming apparatus are second
Be applied to for predetermined voltage secondary transfer printing treatment performed in the state of secondary transfer printing component by voltage source, for will be formed in middle turning
Print the surface that the multiple Color toner images on the surface of component are secondarily transferred to recording materials (for example, paper).Traditional
Image forming apparatus include fixation unit, and toner image of the fixation unit then to being transferred on recording materials is determined
Shadow.
Illustrated such as in Japanese Patent Application Laid-Open No.2001-175092, endless belt is traditionally utilized as intermediate transfer member
(hereinafter referred to as " intermediate transfer belt ").Be exclusively used in first transfer transfer power supply (that is, power circuit) be connected to tensioning member or
First transfer member, the tensioning member is tensioned the inner peripheral surface of intermediate transfer belt.Power circuit is supplied along intermediate transfer belt
Circumferential direction flowing electric current performing first transfer operation.
Intermediate transfer belt is rotated and moved along direction corresponding with the circumferential direction of above-mentioned intermediate transfer belt.According in day
The construction illustrated in present patent application JP No.2001-175092, (that is, opens when from the power supply component being connected with transfer power supply
Tight component or first transfer member) electric current of supply when being flowed along the circumferential direction of intermediate transfer belt, produces the state of partial pressure
Under, form first transfer potential in each first transfer section office.
However, according in Japanese Patent Application Laid-Open No.2001-175092 illustrate construction, in the construction
Electric current performs first transfer operation while flowing along the circumferential direction of intermediate transfer belt, and the first of station is formed in each image
The first transfer potential of transfer section office is significantly influenceed by the resistance value of intermediate transfer belt and with a distance from power supply component.
More specifically, if image forms station being positioned to from power supply component farther out, first transfer potential becomes relatively low.Change
Yan Zhi, may cause to form station in the image being positioned to close to power supply component and be positioned to the image shape from power supply component farther out
Into the difference that first transfer potential between station is larger.If being formed in each image can not suitably maintain first transfer electricity at station
Gesture, then be difficult to for the toner amount of needs to be transferred to intermediate transfer belt.The image being fixed on recording materials can have transfer to lack
Fall into (for example, defect density).
The content of the invention
The present invention relates to a kind of image forming apparatus, described image forms equipment can be worked as during electric current flows to from power supply component
Between transfer belt when prevent from transferring for the first time potential and change in first transfer section office and may insure gratifying first transfer
Characteristic.
According to aspects of the present invention, image forming apparatus include：Multiple images carrier, each described image carrier is delivered
Toner image；Movable conductive intermediate transfer belt, it is first transferred with toner image from multiple images carrier；Multiple
Tight component, its tensioning intermediate transfer belt；Power supply component, it contacts intermediate transfer belt and electric current is supplied into intermediate transfer belt；Connect
Component is touched, its arrangement is between tension members so that contact the intermediate transfer transferred with toner image from multiple images carrier
The first transfer surface side of band；Element is maintained with voltage, it is connected at least one of described tensioning member and contact member.
In the case where electric current flows to intermediate transfer belt from power supply component, the tensioning member and contact member being connected with voltage maintenance element
Maintain predetermined potential or the potential higher than the predetermined potential.
According to another aspect of the present invention, image forming apparatus include：Multiple images carrier, each described image carrier
Delivery toner image；Movable conductive intermediate transfer belt, it is first transferred with toner image from multiple images carrier；For
Electric components, it contacts intermediate transfer belt and electric current is supplied into intermediate transfer belt；Contact member, it is contacted from multiple images carrier
Transferred with the first transfer surface side of the intermediate transfer belt of toner image；Opposition component, its via intermediate transfer belt with confession
Electric components are relative；Element is maintained with voltage, it is connected to contact member.The situation of opposition component is flowed to from power supply component in electric current
Under, maintain the contact member that element is connected to maintain predetermined potential or the potential higher than the predetermined potential with voltage.
According to a further aspect of the invention, image forming apparatus include：Multiple images carrier, each described image carrier
All deliver toner image；Movable conductive intermediate transfer belt, it is first transferred with toner image from multiple images carrier；
Multiple tensioning member, its tensioning intermediate transfer belt；Power supply component, it contacts intermediate transfer belt and electric current is supplied into intermediate transfer
Band；Multiple contact members, its arrangement is between tension members so that contact is from multiple images carrier transferred with toner image
The first transfer surface side of intermediate transfer belt；Element is maintained with voltage, it is connected to multiple contact members.In electric current from power supply structure
In the case that part flows to intermediate transfer belt, multiple contact members that element is connected are maintained to maintain predetermined potential or than described with voltage
Predetermined potential potential high.
Further feature of the invention and aspect will become from detailed description of illustrative embodiments referring to the drawings
Substantially.
Brief description of the drawings
Comprising in this manual and constitute this specification a part accompanying drawing show exemplary embodiment of the invention,
Feature and aspect, together with explanation for explaining principle of the invention.
Fig. 1 schematically shows the image forming apparatus according to the first exemplary embodiment；
Fig. 2 is the block diagram of the various control units for showing the image forming apparatus according to the first exemplary embodiment；
Fig. 3 A and 3B show the construction of the first transfer section according to the first exemplary embodiment；
Fig. 4 A and 4B show measuring system, circumferentially side of the measuring system measurement according to the first exemplary embodiment
To intermediate transfer strip resistance；
Fig. 5 is to show the relation according between the first transfer potential of the first exemplary embodiment and first transfer efficiency
Chart；
Fig. 6 shows forming the first transfer at station before and after recording materials rush at secondary transfer section point in the first image
Intermediate transfer belt potential at part changes with time；
Fig. 7 schematically shows the image forming apparatus according to comparative example 1；
Fig. 8 schematically shows the image forming apparatus according to comparative example 2；
Fig. 9 shows another construction of the image forming apparatus according to the first exemplary embodiment；
Figure 10 shows another construction of the image forming apparatus according to the first exemplary embodiment；
Figure 11 shows to be formed with the relation between potential and transfer supply voltage according to the image of the first exemplary embodiment；
Figure 12 shows exposure control unit and exposing unit；
Figure 13 schematically shows the image forming apparatus according to the second exemplary embodiment；
Figure 14 shows the construction of the first transfer section according to the second exemplary embodiment；
Figure 15 shows another construction of the image forming apparatus according to the second exemplary embodiment；
Figure 16 shows another construction of the image forming apparatus according to the second exemplary embodiment；
Figure 17 shows another construction of the image forming apparatus according to the second exemplary embodiment；
Figure 18 schematically shows the image forming apparatus according to the 3rd exemplary embodiment；
Figure 19 is the chart for showing the relation between secondary transfer printing voltage and intermediate transfer belt potential；
Figure 20 shows another construction of the image forming apparatus according to the 3rd exemplary embodiment；
Figure 21 schematically shows the image forming apparatus according to the 4th exemplary embodiment；
Figure 22 shows to be constructed according to the cleaning of the 4th exemplary embodiment；
Figure 23 is the chart for showing the relation between Transfer current and secondary transfer printing efficiency；
Figure 24 is to show the chart in Transfer current and with the relation between potential；
Figure 25 is the time diagram for showing the transfer process according to the image forming operation of the 4th exemplary embodiment；
Figure 26 shows another construction of the image forming apparatus according to the 4th exemplary embodiment；
Figure 27 shows the image forming apparatus of the modification according to the 4th exemplary embodiment；With
Figure 28 shows the image forming apparatus of the modification according to the 4th exemplary embodiment.
Specific embodiment
Various exemplary embodiments of the invention, feature and method are explained hereinafter with reference to accompanying drawing.
The size of component parts, material, shape and the relative positioning illustrated in following exemplary embodiment can be according to should
Suitably changed with the actual configuration and various conditions of equipment of the invention.Therefore, unless specifically referred to, the present invention is not narrow
It is limited to these embodiments mountain pass, and has allowed various modifications within the scope of the invention.
The mechanical realization according to the image forming apparatus of the first exemplary embodiment and operation referring to Fig. 1 explanations.Fig. 1
Schematically show the example of color image forming.Image forming apparatus according to the present exemplary embodiment are that tandem is beaten
Print machine, its four image for including order arrangement form station " a " to " d ".First image forms station " a " and can form yellow (Y)
Image.Second image forms station " b " and can form magenta (M) image.3rd image forms station " c " and can form cyan (C)
Image.4th image forms station " d " and can form black (Bk) image.Except pending toning in each image formation station
Beyond the color difference of agent, the construction that each image forms station is mutually similar.As representational station, explained in detail below first
Image forms station " a ".
First image forms station " a " to be included：Electrophotographic photosensitive element, it has drum type body (hereinafter referred to as " photosensitive
Drum ") 1a；Charging roller 2a；Developing cell 4a；With cleaning unit 5a.Photosensitive drums 1a is the image-carrier for delivering toner image, institute
Stating photosensitive drums 1a can be rotated along direction indicated by an arrow with predetermined peripheral speed (that is, processing speed).
In addition, developing cell 4a is to store Yellow toner particle to develop with to the yellow toner image on photosensitive drums 1a
Equipment.Cleaning unit 5a can be the component for collecting the toner-particle remained on photosensitive drums 1a.In this exemplary implementation
In example, cleaning unit 5a includes cleaning doctor and toner collecting box as cleaning element, and the cleaning doctor can be contacted
Photosensitive drums 1a, toner-particle of the toner collecting box storage as collected by cleaning doctor.
When controller 100 (that is, control unit) receives picture signal, the first image forms station " a " by making photosensitive drums
1a is rotated along predetermined direction and is started image forming operation.Photosensitive drums 1a is uniform by charging roller 2a in its rotation process
Ground charges with the predetermined potential with predetermined polarity (being in the present example embodiment negative polarity), and photosensitive drums 1a is based on figure
Pass through exposing unit 3a as signal to expose.By aforesaid operations, can be formed and yellow image (i.e., it is contemplated that the image of color)
Corresponding electrostatic latent image.
Next, electrostatic latent image is developed by developing cell (that is, yellow developing unit) 4a, and it is revealed as yellow toning
Agent image.In the present example embodiment, the normal charging polarity of the toner-particle being contained in developing cell is negative polarity.
Electrostatic latent image toner-particle reversibly develops, and the toner-particle has been charged to be had and the sense charged by charging roller
The charging polarity identical polarity of light drum.However, present invention can apply to such electronic photographing device, i.e. the electronics shines
To latent electrostatic image developing, the toner-particle has been charged to the charging pole for having with photosensitive drums to phase equipment toner-particle
The opposite polarity of property.
Intermediate transfer belt 10 passes through multiple tensioning member 11,12 and 13 and is tensioned.Connect with photosensitive drums 1a in intermediate transfer belt 10
In tactile opposition region, intermediate transfer belt 10 along predetermined direction be substantially equal to photosensitive drums 1a rotation peripheral speed traveling
Speed is moved.When image through adjacent part (hereinafter referred to as " the first transfer section photosensitive drums 1a and intermediate transfer belt 10
Point ") when, the yellow toner image being formed on photosensitive drums 1a is transferred to intermediate transfer belt 10 for the first time.
In the present example embodiment, in the state of power supply component contact intermediate transfer belt, electric current is in first transfer behaviour
In work intermediate transfer belt is flowed to from power supply component.It is corresponding that the electric current for being applied forms station in intermediate transfer belt 10 and each image
First transfer section office realize the formation of first transfer potential.Hereinafter illustrate the first transfer electricity according to the present exemplary embodiment
Gesture forming method.
Cleaning device 5a is cleaned and removal is remained on the surface of photosensitive drums 1a without the first toner for transferring
Grain.The photosensitive drums 1a for cleaning can be used for ensuing charging process and image formation treatment.
Similarly, the second image forms station " b " and forms magenta (that is, the second color) toner image.3rd image shape
Cyan (that is, the 3rd color) toner image is formed into station " c ".4th image forms station " d " and forms black (that is, the 4th color)
Toner image.Corresponding toner image is formed at the first transfer section at station in an overlapping manner by phase in corresponding image
It is transferred on intermediate transfer belt 10 after ground.Full-colour image corresponding with the image of expected color can be obtained by above-mentioned treatment.
Then, when four kinds of toner images of color on intermediate transfer belt 10 are passed through by intermediate transfer belt 10 and secondary turn
The secondary transfer section timesharing that print roller 20 is formed, the toner image of four kinds of colors is transferred (that is, secondary transfer printing) in batch
Onto the surface of the recording materials P supplied by paper feeding unit 50.
Secondary transfer roller 20 is operable as secondary transfer printing component.Secondary transfer roller 20 includes the nickel plating of the external diameter with 8mm
Rod iron, the nickel plating rod iron is covered with the external diameter with 18mm by the sponge member for expanding.The sponge member of expansion has 108
The specific insulation of Ω cm and the thickness of 5mm.The main component of the sponge member of expansion is NBR and epichlorohydrin rubber.It is secondary
Transfer roll 20 contacts the outer surface of intermediate transfer belt 10 under the plus-pressure for applying 50N, to form secondary transfer printing part.
When secondary transfer roller 20 is intermediately transferred band 10 to be driven, secondary transfer roller 20 is rotated.When on intermediate transfer belt 10
Toner-particle when being transferred secondarily to recording materials P (for example, paper), transfer power supply 21 (that is, power circuit) is by 2500
The secondary transfer printing voltage of [V] is applied to secondary transfer roller 20.
Transfer power supply 21 includes transformer, and secondary transfer printing voltage can be supplied to secondary transfer roller 20 by the transformer.
Controller 100 controls the output voltage of transformer so that can maintain base from the secondary transfer printing voltage of the transfer supply of power supply 21
Under this constant level.The output voltage for transferring power supply 21 is in the range of from 100 [V] to 4000 [V].
Then, the recording materials P that four kinds of toner images of color are carried thereon is sent in fixing device 30, in institute
State the toner that four kinds of toner images of color in fixing device 30 are melt into blend color by heating and pressurized treatments
Image, and be then fixed on the recording materialp.Remain on intermediate transfer belt 10 without the toner of secondary transfer printing
Grain is cleaned and removed by the cleaning unit 16 including cleaning doctor.Knot when being formed in completion aforesaid operations of panchromatic print image
Beam.
The detailed configuration of controller 100 is illustrated referring to Fig. 2, the controller 100 is performed for image forming apparatus
Various controls.As shown in Figure 2, controller 100 includes CPU (CPU) circuit unit 150.Controller 100 is wrapped
Include read-only storage (ROM) 151 and random access memory (RAM) 152, the read-only storage (ROM) 151 and arbitrary access
Memory (RAM) 152 is two internal memorys.Cpu circuit unit 150 can be according to control journey of the storage in ROM 151
Sequence and control transfer control unit 201, development control unit 202, exposure control unit 203 and charging control unit 204.CPU
Circuit unit 150 is referred to perform treatment from the environmental data table and paper sheet thickness corresponding table of the loadings of ROM 151.Work as CPU
When circuit unit 150 performs various control process, RAM 152 can provisionally store control data and can serve as work
Area.
Transfer control unit 201 can control to transfer power supply 21 so that based on being detected by current detection circuit (not shown)
To current value and the adjusting voltage for the treatment of from the transfer output of power supply 21.If controller 100 receives figure from main frame (not shown)
As information and print command, then cpu circuit unit 150 controls corresponding control unit (that is, to transfer control unit 201, development control
Unit processed 202, exposure control unit 203 and charging control unit 204), corresponding control unit performs image and forms behaviour
Make to realize printing.
Intermediate transfer belt 10, tensioning member 11,12 and 13 and contact member 14 have following construction.
Intermediate transfer belt 10 is operable as intermediate transfer member, the intermediate transfer member along linear extension, to face
Each image of order arrangement forms station " a " to " d ".Intermediate transfer belt 10 is endless belt, and the endless belt is by conductive resin material
It is made, the conductive resin material includes conductive agent addition agent.Intermediate transfer belt 10 is dragged around three tensioning member, described
Three tensioning member are driven roller 11, jockey pulley 12 and secondary transfer printing to edger roll (that is, secondary transfer printing opposition component) 13.Jockey pulley
The tension force of 60N is applied to band 10 by 12.
Intermediate transfer belt 10 can be according to the rotation of the driven roller 11 driven by driving source (not shown) along predetermined party
To rotation so that in the opposition region that intermediate transfer belt 10 is contacted with corresponding photosensitive drums 1a, 1b, 1c and 1d, intermediate transfer
Moved with the gait of march essentially identical with the peripheral speed of corresponding photosensitive drums 1a, 1b, 1c and 1d with 10.
Between two tensioning member (that is, secondary transfer printing is to edger roll 13 and driven roller 11) it is intermediate transfer belt 10, from
The corresponding first linear extension surface transferred with toner image of photosensitive drums 1a, 1b, 1c and 1d, referred to as first transfer surface M.
Metallic roll 14 is operable as the contact member contacted with intermediate transfer belt 10.As shown in fig. 3, the cloth of metallic roll 14
Put the middle position of the direction of motion along intermediate transfer belt 10 between photosensitive drums 1b and photosensitive drums 1c.It is exemplary at this
In embodiment, contact member is in secondary transfer printing to contacting the first transfer table of intermediate transfer belt 10 between edger roll 13 and driven roller 11
Surface side, toner image is transferred at the first transfer surface side of the intermediate transfer belt 10 from multiple photosensitive drums.
Middle position of the metallic roll 14 between the second image forms station " b " and the 3rd image forms station " c " ensures foot
The intermediate transfer belt 10 of enough length is on corresponding photosensitive drums 1b and 1c.Therefore, two ends of metallic roll 14 relative to
The horizontal plane extended between corresponding photosensitive drums 1b and 1c and intermediate transfer belt 10 is maintained at higher along its longitudinal direction
At position.
Metallic roll 14 is made up of nickel plating SUS rods, and the nickel plating SUS rods have the external diameter of 6mm and point-blank extend.Metal
Roller 14 can be intermediately transferred band 10 and drive so that the metallic roll 14 rotates about it axis along the fortune with intermediate transfer belt 10
Dynamic direction identical direction rotates.Metallic roll 14 is arranged on the inner peripheral surface side of intermediate transfer belt 10.Metallic roll 14 along with
The vertical longitudinal direction of the direction of motion of intermediate transfer belt 10 contacts the presumptive area of intermediate transfer belt 10.
In figure 3 a, W represents that the second image forms the photosensitive drums of the photosensitive drums 1b and the 3rd image formation station " c " at station " b "
The distance between 1c, T represent the distance between metallic roll 14 and corresponding photosensitive drums 1b and 1c, H1 represent metallic roll 14 relative to
The hoisting depth of intermediate transfer belt 10.It is the direction of motion between two adjacent axle centers along intermediate transfer belt 10 apart from W
Distance.In the present example embodiment, actual size is W=60mm, T=30mm, and H1=2mm.
In addition, in order to ensure the intermediate transfer belt 10 of sufficient length is on corresponding photosensitive drums 1a and 1d, idler roller
Each in 11 and 13 is relative to the level extended between corresponding photosensitive drums 1a, 1b, 1c and 1d and intermediate transfer belt 10
Face is maintained at position higher, as shown in Figure 3 B.Ensure the intermediate transfer belt 10 of above-mentioned length wound on corresponding photosensitive
On drum 1a and 1d, bring and suppress to go out when the contact when between corresponding photosensitive drums 1a and 1d and intermediate transfer belt 10 is unstable
The effect of existing transfer defect.
In figure 3b, D1 represents the distance between idler roller 13 and photosensitive drums 1a, and D2 represents idler roller 11 and photosensitive drums 1d
The distance between, H2 represents hoisting depth of the idler roller 13 relative to intermediate transfer belt 10, and H3 represents that idler roller 11 is relative
In the hoisting depth of intermediate transfer belt 10.In the present example embodiment, actual size is D1=D2=50mm, and H2=H3
=2mm.
The intermediate transfer belt 10 for being used in the present example embodiment has the girth and 90 μm of thickness of 700mm.In
Between transfer belt 10 be endless belt as made by the polyimide resin mixed with conductive carbon agent.Intermediate transfer belt 10 has electronics
Conductive feature, it is characterised in that the change of resistance value is less when environment temperature/humidity changes.
In addition, in the present example embodiment, the material of intermediate transfer belt 10 is not limited to polyimide resin.Can be used and appoint
What its thermoplastic resin material, for example, polyester, makrolon, polyarylate, acrylonitrile-butadiene-styrene copolymer
(ABS), polyphenylene sulfide (PPS), polyvinylidene fluoride (PVDF) or their hybrid resin.In addition, conductive agent is not limited to carbon.Example
Such as, conductive metal oxide particle can be used.
The specific insulation of the intermediate transfer belt 10 according to the present exemplary embodiment is 1 × 109Ω·cm.By Mitsubishi
The combination of Hiresta-UP (MCP-HT450) and the UR (MCP-HTP12 models) of ring probe type that chemical industry is provided can be used as
For the instrument group of specific insulation measurement.When specific insulation is measured, indoor temperature is set to 23 DEG C and indoor humidity
It is set to 50%.The voltage for being applied is 100 [V], and time of measuring is 10 seconds.Can be used in the present example embodiment
The specific insulation of intermediate transfer belt 10 is from 1 × 107Ω cm to 1 × 1010In the range of Ω cm.
Specific insulation is the index of the electrical conductivity of intermediate transfer belt.Circumferentially the resistance value pair in direction determines to work as electric current
Whether intermediate transfer belt can form desired first transfer potential and (hereinafter referred to as " lead when being flowed practically along circumferential direction
Electric band ") play an important role.
Fig. 4 A show circumferential electric resistance measuring apparatus, and it can be used to measure the electricity along the circumferential direction of intermediate transfer belt 10
Resistance.Shown measurement apparatus include internal roller 101 and driven roller 102 in Figure 4 A, and the internal roller 101 and driven roller 102 exist
Intermediate transfer belt 10 to be measured is interoperatively tensioned in the case of without result in any relaxing.In being made up of metal material
Portion's roller 101 is connected to high voltage power supply 103 (for example, the high voltage power supply model _ 610E provided by Co., Ltd of TREK Japan).Drive
Dynamic roller 102 is grounded.The surface of driven roller 102 is coated with conductive rubber, and the resistance value of the conductive rubber is substantially lower than centre
The resistance value of transfer belt 10.Driven roller 102 rotates about it axis rotation, so that intermediate transfer belt 10 is with the row of 100mm/s
Enter speed motion.
Next, measuring method is described below.The method be included in the driven rolls 102 of intermediate transfer belt 10 drive and
By constant current I in the state of being moved with the gait of march of 100mm/sLIt is supplied to internal roller 101.The method also includes by high-tension electricity
Monitoring voltage [the V of source 103L], the high voltage power supply 103 is connected to internal roller 101.
Fig. 4 B show the equivalent circuit of measuring system shown in Figure 4 A.In figure 4b, RL(=2 [VL]/IL) represent with
The internally edge in the distance between roller 101 and driven roller 102 L (being in the present example embodiment 300mm) corresponding region
The resistance of the circumferential direction 10 of intermediate transfer belt.The method also includes the resistance R that will be calculatedLChange into and intermediate transfer belt
The corresponding value of girth, the girth is suitable with the intermediate transfer belt 10 of 100mm, to obtain the resistance in circumferentially direction.Expect
Be circumferentially direction resistance be equal to or less than 1 × 109Ω is so that electric current flows from power supply component via intermediate transfer belt 10
To each photosensitive drums 1.
The intermediate transfer belt 10 for being used in the present example embodiment has 1 for being obtained by above-mentioned measuring method
×108The resistance in the circumferentially direction of Ω.Used according to the measurement of the intermediate transfer belt 10 of the present exemplary embodiment
Constant current ILIt is 5 μ A.Monitoring voltage [the V for being obtained in the measurementsL] it is 750 [V].Monitoring voltage [VL] being can be in intermediate transfer
The average value of the measured value obtained in the whole girth with 10.Further, since the electricity of the circumferential direction along intermediate transfer belt 10
Resistance RLCan be by formula RL=2 [VL]/ILDefinition, therefore resistance RLEqual to 2 × 750/ (5 × 10-6)=3 × 108Ω.Thus, edge
The resistance for circumferential direction is equal to 1 × 108Ω, it can be by by resulting resistance RLChange into the intermediate transfer with 100mm
Obtained with 10 corresponding values.
The intermediate transfer belt 10 for being used in the present example embodiment is to cause electric current circumferentially direction as described above
The conductive strips of flowing.
The first transfer potential for performing first transfer operation according to the present exemplary embodiment explained in detail below
Forming method.According to the construction of the present exemplary embodiment, predetermined voltage is applied to the secondary transfer printing power supply of secondary transfer printing component
The 21 transfer power supplys that can be used as performing first transfer operation.More specifically, secondary transfer printing power supply 21 can common land be used for just
Secondary transfer and secondary transfer printing.
According to the present exemplary embodiment, secondary transfer roller 20 is operable as power supply component.According to the present exemplary embodiment, two
Secondary transfer is operable as the component that opposes to edger roll 13.Power supply is transferred when secondary transfer printing power supply 21 can serve as described above sharing
When, the cost that can reduce image forming apparatus because the transfer power supply for being exclusively used in first transfer is needed not be provided.
When secondary transfer printing power supply 21 applies a voltage to secondary transfer roller 20, electric current flows to centre from secondary transfer roller 20
Transfer belt 10.While the electric current for flowing through intermediate transfer belt 10 flows along the circumferential direction of intermediate transfer belt 10, the electricity
Stream charges to intermediate transfer belt 10, so as to form first transfer potential in each first transfer section office.When in first transfer electricity
When producing electrical potential difference between gesture and photosensitive drums potential, the toner of corresponding photosensitive drums 1a, 1b, 1c and 1d moves to intermediate transfer
Band 10 is realizing first transfer operation.
Fig. 5 is the chart for showing the relation between intermediate transfer belt potential and first transfer efficiency.In Figure 5, ordinate
Transfer efficiency value is referred to, the transfer efficiency value is to transmit reflection densitometer (being provided by GretagMacbeth) with Macbeth
The measurement result of the first transfer remnants density for measuring.When ordinate value is bigger, the first remaining density of transfer is higher.Cause
This, transfer efficiency reduction.In the construction according to the present exemplary embodiment, if the chart as shown in Fig. 5 is it is clear that wherein
The region of gratifying first transfer efficiency can be obtained (for example, can wherein obtain 95% or higher transfer efficiency
Region) there is the first transfer potential of 150 [V] to 450 [V].
However, in first transfer operation, electric current flows to phase from intermediate transfer belt 10 in corresponding first transfer section office
Photosensitive drums 1a, 1b, 1c and the 1d for answering.Therefore, can be difficult to for first transfer potential to maintain desired potential.For example, being arranged in
Station " c " and " d " is formed along the image on the downstream of the direction of motion of intermediate transfer belt 10 (that is, to be supplied from secondary transfer roller 20
Electric components) farther out.In addition, the region for reaching the intermediate transfer belt 10 that downstream image forms station " c " and " d " is to have made electric current
Flow to the region that upstream side image forms the photosensitive drums at station " a " and " b ".
Therefore, the first transfer potential in downstream transfer section office is intended to less than in the first of upstream side transfer section office
Secondary transfer potential.In addition, when electric current flows along the circumferential direction of intermediate transfer belt 10, due to the electricity of intermediate transfer belt 10
, there is voltage drop in resistance.Therefore, the first transfer potential in downstream transfer section office is intended to be less than in upstream side transfer section
The first transfer potential at place.
If can be formed downstream image from the electric current of the supply of secondary transfer roller 20 packs the first transfer potential of foot,
Upstream side image forms the first transfer potential increase at station, and will not obtain desired transfer efficiency.It is thus impossible at each
First transfer section office maintains desired first transfer potential, and transfer defect occurs.
Therefore, the secondary transfer printing of first transfer surface M of intermediate transfer belt 10 is interoperatively formed to edger roll 13 and drive
Dynamic roller 11 maintains element 15 to be grounded via voltage.When electric current from secondary transfer roller 20 (that is, power supply component) via intermediate transfer belt
10 flow to voltage maintain element 15 when, be connected to voltage maintain element 15 secondary transfer printing edger roll 13 and driven roller 11 are maintained
In predetermined potential or the potential higher than the predetermined potential.Predetermined potential is previously set, first so as to maintain each
First transfer potential required for the desired transfer efficiency of transfer section office acquisition.
In addition, the contact member contacted with intermediate transfer belt 10 be arranged in secondary transfer printing to edger roll 13 and driven roller 11 it
Between formed intermediate transfer belt 10 first transfer surface M side on.The contact member for being used in the present example embodiment
It is metallic roll 14.Metallic roll 14 maintains the electrical ground of element 15 via voltage.
It is Zener diode (that is, constant voltage elements) that the voltage for being used in the present example embodiment maintains element 15.
In below illustrating, Zener voltage is referred to when the voltage of opposite polarity is applied to Zener diode 15 between the anode and cathode
Voltage.
When it is Zener diode that voltage maintains element 15, it might be useful to by the absolute value of the Zener voltage of Zener diode
It is set to predetermined potential (for example, 150 [V]) or the potential higher than the predetermined potential.Therefore, Zener voltage is set to 300 [V]
To maintain predetermined voltage or the voltage higher than the predetermined voltage.
When voltage is applied to secondary transfer roller 20 from secondary transfer printing power supply 21, electric current is from secondary transfer roller 20 via centre
Transfer belt 10 and secondary transfer printing flow to Zener diode 15 to edger roll 13, and the Zener diode 15 is grounded.In this case, because
For electric current flows to anode-side from cathode side, so the voltage of opposite polarity is applied to Zener diode 15.Zener diode 15
Anode-side is grounded.Therefore, the cathode side of Zener diode 15 maintains Zener voltage.Therefore, it is connected to Zener diode 15
The secondary transfer printing of cathode side maintains 300 [V] to edger roll 13 and driven roller 11.Metallic roll 14 is connected to Zener diode 15.Cause
This, with secondary transfer printing to edger roll 13 and driven roller 11 similarly, metallic roll 14 can maintain 300 [V].
Therefore, maintaining the metallic roll 14 of the Zener voltage of 300 [V] causes the first transfer surface M of intermediate transfer belt 10
At least part of region potential in 300 [V] to be maintained.In addition, when secondary transfer printing maintains 300 to edger roll 13 and driven roller 11
When [V], intermediate transfer belt 10 can first transfer surface along the direction of motion of intermediate transfer belt 10 upstream end thereof position
With the potential that 300 [V] are maintained at the Liang Ge positions of downstream end position.
As described above, intermediate transfer belt maintains predetermined potential or more pre- than described at multiple positions of intermediate transfer belt 10
Determine potential potential high.Therefore, even if being difficult to by via the contact site between secondary transfer roller 20 and intermediate transfer belt 10
Supplied electric current is divided to maintain to transfer potential for the first time, it is also possible to from secondary transfer printing to edger roll 13, driven roller 11 or metallic roll 14
Contact portion supply enough electric current.
In the present example embodiment, the jockey pulley 12 for applying tension to intermediate transfer belt 10 is connected to voltage maintenance unit
Part (that is, Zener diode 15).Above-mentioned construction according to the present exemplary embodiment can prevent electric current from flowing to ground from jockey pulley 12.
Jockey pulley 12 is not the component contacted with the first transfer surface M of intermediate transfer belt 10.Therefore, it might be useful to make the electricity of jockey pulley 12
Insulation.
Voltage maintains element to carry out following effect with the connect band of each component as described above.First, Zener diode 15
Following effect is come to the connect band of edger roll 13 with secondary transfer printing.Fig. 6 show recording materials P be flushed to secondary transfer section point before with
The potential for changing over time that the first transfer section office for forming station in the first image afterwards measures.In figure 6, ordinate refers to
Be the potential that the first transfer section office at station is formed in the first image, and abscissa refers to elapsed time.
Measurement result shown in Fig. 6 is applied to the voltage for changing over time of intermediate transfer belt 10, the measurement knot
Fruit is measured during according to the treatment of the secondary transfer printing of the present exemplary embodiment.Instrument used in measurement include by
Surface potential measuring apparatus (model 370) and dedicated probe (model 3800S-2) that Co., Ltd of TREK Japan provides.In Zener
Diode 15 is connected to secondary transfer printing and measurement performed in the state of edger roll 13 is arranged in and secondary transfer printing pair including monitoring
The potential of the metallic roll (not shown) at position that edger roll 13 is spaced apart via intermediate transfer belt 10 is measuring intermediate transfer belt 10
Surface potential.
Dotted line in Fig. 6 indicates resulting under conditions of Zener diode 15 is not connected to secondary transfer printing to edger roll 13
Reference measurements.Solid line in Fig. 6 indicates the gained under conditions of Zener diode 15 is connected to secondary transfer printing to edger roll 13
The measurement result for arriving.
If carrying out current constant control when recording materials P is flushed to secondary transfer section timesharing, supplied from secondary transfer roller 20
The magnitude of current given instantaneously increases.In this case, excessive electric current (that is, the one of the electric current for being applied from secondary transfer roller 20
Part) Zener diode 15 can be flowed through to edger roll 13 via intermediate transfer belt 10 and secondary transfer printing.The table of intermediate transfer belt 10
Face potential can be stablized at desired level (for example, 200 [V]).
However, being not connected under comparable situation of the secondary transfer printing to edger roll 13 in Zener diode 15, it is impossible to obtain above-mentioned
Effect.Therefore, after recording materials are flushed to secondary transfer section point, in the first transfer section office that the first image forms station
Between transfer belt potential produce significant change.
Even if as described above, when recording materials have arrived at secondary transfer section timesharing secondary transfer current suddenly change, together
Diode 15 of receiving can also bring the first transfer for stably maintaining the first image to form station with connection of the secondary transfer printing to edger roll 13
The effect of the intermediate transfer belt potential at part.
Next, Zener diode 15 (that is, is arranged in the structure in region corresponding with first transfer surface with metallic roll 14
Part) connect band come following effect.Comparative example is used to verify these effects.
It is similar with intermediate transfer belt 10 described in the present example embodiment, used in each comparative example in
Between transfer belt be have 1 × 108The conductive strips of the resistance in the circumferentially direction of Ω.Figure used in each comparative example
There is the processing speed of 100mm/s as formation equipment.In order to confirm these effects, in the present example embodiment and following two
The intermediate transfer belt potential at each image formation station during first transfer operation is measured in each in individual comparative example.
Instrument used in intermediate transfer belt potential measurement includes that the surface potential measurement provided by Co., Ltd of TREK Japan sets
Standby (model 370) and dedicated probe (model 3800S-2).At each first transfer section on the back side of intermediate transfer belt 10
Measurement intermediate transfer belt potential.
Fig. 7 and 8 shows the construction of corresponding comparative example.The evaluation knot of comparative example is explained referring to table 1
Really.
【Comparative example 1】
According to the construction of image forming apparatus shown in the figure 7, secondary transfer printing (that is, forms first transfer to edger roll 13
The component on surface) electrical ground, and the transfer power supply for being exclusively used in transferring for the first time is connected to driven roller 11.Thus, electric current is from connection
Transfer power supply to driven roller 11 flows to secondary transfer printing to edger roll 13 via intermediate transfer belt 10 so that for first transfer
Each first transfer section office produces first transfer potential.
Roller component 17a, 17b, 17c and 17d are arranged at opposition region, the face of intermediate transfer belt 10 at the opposition region
To photosensitive drums 1a, 1b, the 1c and 1d at corresponding station.Each roller component contact intermediate transfer belt 10 and corresponding photosensitive drums with
Form first transfer section.Corresponding roller component 17a, 17b, 17c and the 17d being maintained under electrically floating state are included with 5mm
The elastic sponge of the metallic roll of diameter and the thickness with 2mm, the elastic sponge covers metallic roll.Corresponding roller component 17a,
17b, 17c and 17d are intermediately transferred band 10 and drive so that rotate about it axis and synchronously turn with the rotation of intermediate transfer belt 10
It is dynamic.In the figure 7 described in the remainder of the construction of shown image forming apparatus and the first exemplary embodiment (referring to Fig. 1)
Those be similar to.
【Comparative example 2】
According to the construction of image forming apparatus shown in fig. 8, (it has the Zener electricity of 300 [V] to Zener diode 19
Pressure) secondary transfer printing is connected to edger roll 13 (that is, forming the component of first transfer surface), and the electrical ground of driven roller 11.Thus,
Electric current flows to secondary transfer printing to edger roll 13 from secondary transfer printing power supply 21 via intermediate transfer belt 10.Secondary transfer printing is connected to edger roll
13 Zener diode can maintain 300 [V].In addition, electric current from secondary transfer roller 20 along intermediate transfer belt 10 circumference
Flow in direction so that produce first transfer potential in each the first transfer section office for first transfer.
Now, idler roller 13 has and the corresponding potential of Zener diode 19 (that is, 300 [V]).Started with above-mentioned potential,
Image forming apparatus form in each image according to intermediate transfer belt potential and first transfer operation are performed at station.With comparative example 1
Similar, roller component 17a, 17b, 17c and 17d are arranged in and corresponding photosensitive drums 1a, 1b stood, the corresponding opposition regions of 1c and 1d
Place.The remainder of the construction of shown image forming apparatus is similar with those described in comparative example 1 in fig. 8.
Next, illustrating evaluation result below.Table 1 shows to be existed according to above-mentioned example embodiment and two comparative example
The measurement result of the intermediate transfer belt potential during image forming operation.
According to the construction of comparative example 1, when electric current flows to secondary transfer printing to edger roll 13 from driven roller 11, because centre turns
There is voltage drop with 10 resistance in print.In addition, when electric current is leaked via each photosensitive drums, there is voltage drop.Therefore, image
The first transfer potential for forming station " a " (that is, be positioned at secondary transfer printing and form station to the image near edger roll 13) gets lower than figure
First transfer potential as forming station " d " (that is, be positioned at the image near driven roller 11 and form station).
For example, in the construction of comparative example 1, if the voltage for applying 600 [V] from transfer power supply is stood so that image is formed
The first transfer potential of " a " is set to 150 [V] or higher, then because the 4th image forms station " d " (black) and is positioned at transfer electricity
Source nearby makes the 4th image form the intermediate transfer belt potential at station " d " place as value (for example, 500 [V]) very high.As schemed
Shown in 5, if intermediate transfer belt potential deviates from desired potential region, transfer efficiency deteriorates.Institute's shape in this case
Into transfer be so powerful and cause occur electric discharge in first transfer section.The electric discharge changes toner to be transferred
Polarity.As a result, the amount to be transferred to the toner-particle of intermediate transfer belt 10 is reduced, and forms station " d " in the 4th image
There is defect density in (black).
According to the construction of comparative example 2, electric current flowed to via intermediate transfer belt 10 from secondary transfer roller 20 be connected to it is secondary
Transfer the Zener diode 19 to edger roll 13.When the electric current of flowing is more than or equal to constant amount, Zener diode 19 is maintained
In the Zener voltage of 300 [V], and secondary transfer printing is also maintained the voltage of 300 [V] to edger roll 13.Therefore, first stop " a "
(that is, upstream station) can maintain the intermediate transfer belt potential of 200 [V].
However, the intermediate transfer belt potential at trip station falls below the level of predetermined potential (150 [V]) in each of the lower.
As a result, form station " c " (cyan) in the 3rd image because transfer field dies down and the 4th image forms station " d " (black) place and occurs
Transfer defect.
The difference of the construction according to the present exemplary embodiment (referring to Fig. 1) is that metallic roll 14 is arranged in the second figure
As being formed between station " b " and the 3rd image formation station " c ", and interoperatively it is tensioned roller 11,12 and of intermediate transfer belt 10
13 are grounded via Zener diode 15.Thus, the construction according to the present exemplary embodiment can maintain 300 at each roller segment
The Zener voltage of [V].
Table 1 is included according to comparative example 1, comparative example 2 and the present exemplary embodiment in first to fourth first transfer
Potential at part.As shown in Table 1, the fabulous aspect of the construction according to the present exemplary embodiment is that each is first
The change of transfer section office can be suppressed to allow all first transfer potentials maintain predetermined potential (150 [V]) or
The potential (that is, potential obtain desired transfer efficiency required for) higher than the predetermined potential.
Table 1
| First | Second | 3rd | 4th | |
| Comparative example 1 | 200[V] | 200[V] | 400[V] | 500[V] |
| Comparative example 2 | 200[V] | 150[V] | 100[V] | 50[V] |
| Exemplary embodiment | 180[V] | 220[V] | 220[V] | 150[V] |
As described above, the image forming apparatus according to the present exemplary embodiment include being connected to the metal of Zener diode 15
Roller 14, its middle position between the second image forms station " b " and the 3rd image forms station " c ", the metallic roll 14 is led to
Crossing makes electric current along the circumferential direction flowing of intermediate transfer belt 10 as the main construction for forming first transfer potential
Subelement.Thus, the image forming apparatus according to the present exemplary embodiment can prevent from transferring potential for the first time first at each
Transfer section office changes, and electric current can be caused to flow to intermediate transfer belt from power supply component, so that it is guaranteed that gratifying first
Secondary transferring properties.
As described above, the metallic roll 14 for being used in the present example embodiment is made up of nickel plating SUS rods.However, metal
Roller 14 is not limited to above-mentioned example.For example, metallic roll 14 can be made up of other metals (for example, aluminium or iron) or can be conductive tree
Fat roller.In addition, because similar effect can be obtained, metallic roll 14 can be coated with elastic component.
The voltage maintenance element for being used to stablize intermediate transfer belt potential in the present example embodiment is Zener diode 15
(that is, constant voltage elements).However, it is possible to it is available to bring other constant voltage elements (for example, rheostat) of similar effect.In addition,
The resistive element that first transfer potential can be maintained into predetermined potential or the potential higher than the predetermined potential is available.Example
Such as, it might be useful to use the resistive element of 100M Ω.However, maintained in the case that element is resistive element in voltage, potential according to
Change according to the magnitude of current for flowing through resistive element.Therefore, compared with above-mentioned constant voltage elements, management potential becomes difficult.
In addition, can be used multiple voltage to maintain element.Element is maintained (referring in this exemplary implementation using shared voltage
Example described in voltage maintain element 15) useful part be that the component of all connections is (for example, driven roller 11, secondary transfer printing
To edger roll 13 and metallic roll 14) identical potential can be maintained.Furthermore, it is possible to be arranged on any connection by by resistive element
Component and voltage maintain be provided with what the component that resistive element is connected was connected with no resistive element between element 15
Apply electrical potential difference between component.
In addition, as described above, only one metallic roll (that is, metallic roll 14) is arranged in the second image forms station " b " and the 3rd
Image is formed between station " c ".However, metallic roll 14 can be arranged in the first image forms station " a " with the 4th image formation station
Between any position at.In addition, as shown in Figure 9, multiple metallic rolls can be arranged in the first image and form station " a " and the 4th figure
As between formation station " d ".More specifically, metallic roll 14a is arranged in the first image forms station " a " with the second image formation station " b "
Between.Metallic roll 14b is arranged in the second image and is formed between station " b " and the 3rd image formation station " c ".In addition, metallic roll 14c cloth
Put between the 3rd image forms station " c " and the 4th image forms station " d ".
As described in the present example embodiment, station " b " and the is formed when only one metallic roll 14 is arranged in the second image
When between three images formation station " c ", can be formed in the basic center of first transfer surface M and maintain predetermined potential or than described in
The region of predetermined potential potential high.In other words, or even when the quantity of metallic roll is smaller it is also possible to prevent to transfer potential for the first time
Change.
In addition, contact member can be arranged in secondary transfer printing between edger roll 13 and driven roller 11, the secondary transfer printing pair
Edger roll 13 and driven roller 11 interoperatively form the first transfer surface M of intermediate transfer belt 10 so that in contact member contact
Between transfer belt 10 outer surface.For example, as the side for making contact member be contacted with the outer surface of intermediate transfer belt 10
Method, contact member can be arranged in the end in a longitudinal direction of intermediate transfer belt 10.
In addition, used as adoptable arrangement, power supply component can be arranged to not face the tensioning for forming first transfer surface M
Component.For example, it might be useful to using the image forming apparatus shown in Figure 10, even if powering structure in described image formation equipment
Part is secondary transfer roller 20 and the component that opposes is secondary transfer printing to edger roll 13, secondary transfer printing to edger roll 13 also not with first transfer
Surface M is contacted.In even shown in Fig. 10 construction, electric current can be from secondary transfer roller 20 via intermediate transfer belt 10 and two
Secondary transfer is supplied directly to Zener diode 15 to edger roll 13.Therefore, the metallic roll 14 for being contacted with first transfer surface M can be tieed up
Hold in predetermined potential or the potential higher than the predetermined potential.
Explained referring to time diagram shown in fig. 11 and formed in the image according to the present exemplary embodiment
Between the secondary transfer printing voltage with potential and as produced by transfer power supply in the operation of first and secondary transfer printing in operation
Relation.
In response to the picture signal supplied from controller 100, image forming apparatus start image forming operation.Transfer control
The control of unit 201 transfer power supply 21 starts applied voltage V2 with before first transfer operation is started in timing S1.Thus, every
Individual first transfer section office forms potential V1.Potential V1 is more than or equal to first required for for the desired transfer efficiency of acquisition
Transfer potential.In the present example embodiment, as the setting for forming potential V1, transfer voltage V2 is set to 2000V.
Then, in timing S2, the first image forms station and starts first transfer operation (that is, toner image is from the quilt of photosensitive drums 1
One after the other it is transferred to intermediate transfer belt 10).In timing S3, the toner image delivered by intermediate transfer belt 10 reaches secondary transfer printing
Part.This moment, transfer control unit 201 makes transfer power supply 21 change over for needed for execution secondary transfer printing operation transfer voltage
The voltage V3 for wanting.Thus, toner image can be transferred to recording materials.For example, this moment, transfer voltage V3 is set to 2500V.
Next, in timing S4, image forming apparatus terminate first transfer operation.Then, in timing S5, image is formed and set
It is standby to terminate secondary transfer printing operation (that is, terminating image forming operation).
Even when the transfer control transfer power supply of control unit 201 is with according to the every of image forming operation as shown in Figure 11
During its output voltage of individual phasic change, it is also possible to maintain element to maintain the potential of intermediate transfer belt by voltage.
Example according to Figure 11, transfer control unit 201 performs the Isobarically Control for transferring power supply 21.Or
Person, transfer control unit 201 can perform current constant control, to flow constant current.
In addition, if corresponding photosensitive drums 1a, 1b, 1c and 1d long periods are repeatedly subjected to the electric discharge of charging roller 2, then often
Individual photosensitive drum surface is all deteriorated.In addition, the film thickness of photosensitive drum surface is because photosensitive drum surface and cleaning device 5 are frictionally engaged
It is incrementally decreased.If use state (for example, rotation number of turns of accumulation) mutually different photosensitive drums are combined into bulging group, this
The film thickness of a little photosensitive drums is differed.
If charging voltage Vcdc constant in this condition is applied to corresponding photosensitive drums, the charging of photosensitive drum surface
Potential Vd usually because potential difference resulted in air gap between charging roller 2 and photosensitive drums 1 and change.If each
The charged electric potential Vd changes of photosensitive drum surface, then transfer contrast and (that is, turn with middle in photosensitive drums 1 at first transfer section
Print with the electrical potential difference between 10) accordingly change.
As a kind of feasible method, the electricity of each first transfer section can be changed according to the change of charged electric potential Vd
Gesture.However, in the construction according to the present exemplary embodiment, it is difficult to formed in each image and first transfer is arbitrarily set at station
Partial potential.
Accordingly, as another feasible method, controller 100 can change corresponding according to operating environment or use state
Charging roller 2a, 2b, 2c and 2d charging voltage so that the charged electric potential Vd of photosensitive drum surface is balanced.In such a case it is possible to
Suitably maintain to transfer contrast for the first time in each first transfer section office.
In addition, as the method for reducing cost, shared charge power supply can be set and arrived with by charging voltage output
Each charging roller.In this case, it might be useful to which controller 100 controls corresponding exposing unit 3a, 3b, 3c and 3d.Work as exposure
When unit 3a, 3b, 3c and 3d form electrostatic latent image according to picture signal, can be by making corresponding photosensitive drums 1a, 1b, 1c and 1d
Non-image surface region be evenly exposed to dim light and stabilization photosensitive drums potential.
Used as the example of the weak exposure of non-image surface region, being explained referring to Figure 12 can be by the first image
Form the operation that the exposing unit 3a at station " a " is performed.The picture signal for being sent from controller 100 in fig. 12 is along depth side
To the multi-valued signal (0 to 255) being classified with 8 (=256).When image signal value is 0, laser beam is closed.When image letter
When number value is 255, laser beam is opened completely.If picture signal has median (that is, in 1 to 254 any one), then laser
Beam has middle power corresponding with image signal value.
The exposure levels of non-image portion office can be arbitrarily set at according to the level of multi-valued signal.In following explanation
In, thus it is speculated that go out, when non-image portion exposes, the level set of multi-valued signal to 32.If signal value is 0 (its non-figure of instruction
As part), then changed by the picture signal being arranged in exposure control unit 203 from the picture signal of the transmission of controller 100
Circuit 68a and change into 32.If its value is any one in 1 to 255, picture signal is compressed to be changed into 33 to 255
Correspondence one.
Then, the output of signaling conversion circuit 68a changes into serial time direction of principal axis and believes by frequency modulation circuit 61a
Number.In the present example embodiment, the signal for being converted by frequency modulation circuit 61a can be used in the resolution with 600 points/inch
In the pulse width modulation of each point pulse of rate.
Laser driver 62a is driven in response to the output signal of frequency modulation circuit 61a.Laser driver
62a causes laser diode 63a to launch laser beam 6a.Laser beam 6a is arrived through correction optical system 67a and as scanning light
Up to photosensitive drums 1a.Correction optical system 67a includes polygonal mirror 64a, lens 65a and bending mirror 66a.As the example of modification, frequency
Rate modulation circuit 61a can be arranged in controller (that is, with the device of laser driver 62a independences).
As described above, it is effective non-image portion is exposed for stablizing photosensitive drums potential.Thus, even if when each sense
During the film thickness change of light drum, it is also possible to be appropriately performed first transfer operation.
In above-mentioned first exemplary embodiment, voltage maintains element to be connected to secondary transfer printing to edger roll 13, driven roller 11
With metallic roll 14, so as to prevent potential from changing in each first transfer section office.On the contrary, in the second exemplary embodiment
In be provided with multiple contact members.Sum and the image-carrier (that is, photosensitive drums 1a, 1b, 1c and 1d) of contact member to be placed
Quantity correspondence.Voltage maintains element to be connected to these contact members.According to the image forming apparatus of the second exemplary embodiment
Construction remainder it is similar with those described in the first exemplary embodiment.Therefore, identical reference is indicated
Similar component.
The hardware construction according to the present exemplary embodiment is explained referring to Figure 13 and 14.Figure 13 is to show basis
The schematic cross sectional views of the image forming apparatus of the present exemplary embodiment.
As shown in Figure 13, the construction according to the present exemplary embodiment includes metallic roll 23a, 23b, 23c and 23d, its cloth
Put on the downstream of corresponding first transfer section, so that metallic roll 23a, 23b, 23c and 23d are via intermediate transfer belt 10
In face of corresponding photosensitive drums 1a, 1b, 1c and 1d.Interoperatively it is tensioned three idler rollers 11,12 and 13 of intermediate transfer belt 10
With above-mentioned metallic roll 23a, 23b, 23c and 23d via (that is, the constant pressure unit of Zener diode 15 for being operable as voltage maintenance element
Part) ground connection.
The detailed configuration of above-mentioned metallic roll is illustrated referring to Figure 14.Figure 14 is that the first shown in fig. 13 image is formed
Stand " a " construction partial enlarged drawing.In fig. 14, metallic roll 23a is arranged on the downstream of photosensitive drums 1a and from photosensitive
The center of drum 1a offset by 8mm along the direction of motion of intermediate transfer belt 10.In addition, the roller bearing of metallic roll 23a is maintained at phase
Horizontal plane for extending between photosensitive drums 1a and 1b and intermediate transfer belt 10 is increased at the position of 1mm, to ensure foot
The intermediate transfer belt 10 of enough length is on photosensitive drums 1a.
Metallic roll 23a, 23b, 23c and 23d are positioned near corresponding photosensitive drums 1a, 1b, 1c and 1d, but with it is corresponding
Photosensitive drums 1a, 1b, 1c and 1d are fully spaced, and so as to stablize intermediate transfer belt potential, and prevent metallic roll 23a, 23b, 23c
Corresponding photosensitive drums 1a, 1b, 1c and 1d are damaged with 23d.Along the direction of motion of intermediate transfer belt 10, metallic roll 23a, 23b and
23c is positioned on their downstream of corresponding first transfer section.In addition, each metallic roll is positioned to from corresponding first
Transfer section is nearer, and from the neighboring photosensitive drum 1 being arranged on downstream farther out.
In addition, metallic roll 23d is positioned on the downstream of its corresponding first transfer section.Metallic roll 23d be positioned to from
Corresponding first transfer section is nearer, and from the adjacent driven roller 11 being arranged on downstream farther out.
In fig. 14, W represents that the first image forms the photosensitive drums of the photosensitive drums 1a and the second image formation station " b " at station " a "
The distance between 1b, K represent the offset distance at centers of the metallic roll 23a relative to photosensitive drums 1a, and H4 represents metallic roll 23a
Relative to the hoisting depth of intermediate transfer belt 10.In the present example embodiment, actual size is W=60mm, K=8mm, and
H4=1mm.
Similar with the first exemplary embodiment, metallic roll 23a is made up of nickel plating SUS rods, and the nickel plating SUS rods have 6mm
External diameter and point-blank extend.Metallic roll 23a can be intermediately transferred band 10 and drive so that 23a is around its turn for the metallic roll
Shaft line is rotated along the direction of motion identical direction with intermediate transfer belt 10.Metallic roll 23a along with intermediate transfer belt 10
The vertical longitudinal direction of the direction of motion contact the presumptive area of intermediate transfer belt 10.
It is arranged in the metallic roll 23b that the second image is formed on station " b ", the metal being arranged on the 3rd image formation station " c "
Roller 23c and the metallic roll 23d being arranged on the 4th image formation station " d " have the construction similar with the construction of metallic roll 23a.Root
Those described in remainder and the first exemplary embodiment according to the construction of the image forming apparatus of the present exemplary embodiment
It is similar.Therefore, the explanation of its redundancy will be avoided.When transfer power supply 21 apply a voltage to secondary transfer roller 20 when, electric current via
Intermediate transfer belt 10 flows to secondary transfer printing to edger roll 13 (that is, secondary transfer printing opposition component).While electric current flowing, Zener two
Pole pipe 15 can maintain Zener voltage.When Zener diode 15 maintains Zener voltage, the corresponding of Zener diode 15 is connected to
Metallic roll 23a, 23b, 23c and 23d can maintain Zener voltage.
Voltage maintenance element (that is, Zener diode 15) will be arranged near corresponding first transfer section as described above
Metallic roll 23a, 23b, 23c and 23d maintain predetermined voltage or the voltage higher than the predetermined voltage (that is, 300 [V] or more
It is high).Therefore, the region near each first transfer section of intermediate transfer belt 10 can maintain desired potential (for example,
150 [V]) or potential higher.Therefore, it is possible to make the change of the first transfer potential of each first transfer section office minimize simultaneously
And may insure gratifying first transferring properties.
In addition, according to above-mentioned construction, the potential for each first transfer section can be formed.Therefore, with larger
Circumferentially the conductive strips (that is, in the band of corresponding first transfer section office potential significant change) of the resistance value in direction can be used as
Intermediate transfer belt 10 in the present exemplary embodiment.
If intermediate transfer belt 10 has less resistance value, flowing through the electric current of band can increase into so that first transfer
Toner image flies off from band.On the other hand, if there is intermediate transfer belt 10 larger resistance value to be flown off with solving toner,
The electric current for then being flowed along the circumferential direction of intermediate transfer belt 10 is significantly reduced, but can also suppress above-mentioned phenomenon.At this
In aspect, increased number of contact member is used to realize gratifying first transfer.
According to construction described in the present example embodiment, each metallic roll is all disposed within corresponding first transfer section
Downstream on.In other words, each metallic roll is positioned on relatively low band potential side, because current segment ground is flowed into often
In individual photosensitive drums 1.Therefore, it can increase electrical potential difference to be formed between first transfer section and metallic roll, and can make
People satisfactorily supplies electric current.In this aspect, each metallic roll is arranged on the downstream of corresponding first transfer section than every
Individual metallic roll is arranged in more useful on upstream side.
Can be applied to the above-mentioned construction of the present exemplary embodiment of each first transfer section includes contact member, described to connect
Tactile component is positioned at the opposition position with corresponding photosensitive drums 1a, 1b, 1c and 1d on the downstream of scheduled volume.However, can
Using other constructions.For example, as shown in Figure 15, each contact member can be arranged in below corresponding photosensitive drums.At this
In the case of, it is necessary that opposition component 22a, 22b, 22c and 22d is contacted with fixation with corresponding photosensitive drums 1a, 1b, 1c and 1d
First transfer section.Therefore, the contact member that can be used in this case is, for example, the roller that its surface is coated with elastic conducting layer.
As another adoptable construction, as shown in Figure 16, metallic roll is not provided near photosensitive drums 1a, but
It is into relativeness and corresponding from its that three metallic rolls 23b, 23c and 23d are arranged to corresponding photosensitive drums 1b, 1c and 1d
Photosensitive drums 1b, 1c and 1d offset by predetermined amount.Metallic roll 23b, 23c and 23d and idler roller 11,12 and 13 are via Zener two
Pole pipe 15 is grounded.
Image forms station " a " (yellow) and is positioned near power supply component 20, as described in the first exemplary embodiment.Cause
This, compared with other images form station, when electric current is supplied from secondary transfer roller 20, image forms station " a " and will easily turn for the first time
Print potential is maintained under gratifying level.In other words, can remove and form that station " a " (yellow) is corresponding above-mentioned to be connect with image
Component (that is, metallic roll 23a) is touched to reduce the cost of image forming apparatus.
In addition, as other adoptable constructions, the construction shown in Fig. 3 may be modified as so that driven roller 11 (i.e.,
Form the roller of first transfer surface M) insulated (to allow driven roller 11 to be electricity with Zener diode 15 as shown in Figure 17
Insulation).
In this case, metallic roll 23d (that is, being positioned at the roller near first transfer section) supplies compensation electric current so that
The image that maintenance is positioned near driven roller 11 forms the first transfer potential at station " d ".As shown in Figure 17, each metallic roll 23
Zener is connected to secondary transfer printing opposition component 13 (that is, the component relative with secondary transfer roller 20 via intermediate transfer belt 10)
Diode 15 (that is, voltage maintains element).Therefore, the construction shown in Figure 17 can bring similar with the construction shown in Figure 13
Effect.In addition, if the electrical conductivity of intermediate transfer belt 10 is relatively low, then usefully will only secondary transfer printing to the He of edger roll 13
Metallic roll 23d is connected to Zener diode 15.
In addition, contact member can be arranged in the two of the first transfer surface M for interoperatively forming intermediate transfer belt 10
Secondary transfer is between edger roll 13 and driven roller 11 so that contact member contacts the outer surface of intermediate transfer belt 10.For example, conduct
Method for making contact member be contacted with the outer surface of intermediate transfer belt 10, contact member can be arranged in intermediate transfer belt
10 end in a longitudinal direction.
It is similar with the first exemplary embodiment, in the present example embodiment for stablizing the voltage of intermediate transfer belt potential
It is Zener diode 15 (that is, constant voltage elements) to maintain element.However, it is possible to bring similar effect other constant voltage elements (for example,
Rheostat) it is available.Furthermore it is possible to first transfer potential is maintained into predetermined potential or the potential higher than the predetermined potential
Resistive element be available.For example, it might be useful to use the resistive element of 100M Ω.However, it is electricity to maintain element in voltage
In the case of resistance element, potential foundation flows through the magnitude of current of resistive element and changes.Therefore, compared with above-mentioned constant voltage elements, pipe
Reason potential becomes difficult.
In addition, it is available that multiple voltages maintain element.Element is maintained (referring in this exemplary reality using shared voltage
Apply voltage described in example and maintain element 15) useful part be, the component of all connections (for example, driven roller 11, secondary turn
Print is to edger roll 13 and metallic roll 24) identical potential can be maintained.
Construction according to the first and second exemplary embodiments, the Zener diode for maintaining element as voltage will
The potential of the component (that is, tensioning member and contact member) of each connection is maintained under positive electricity level.In the 3rd exemplary implementation
In example, tensioning member and contact member are connected to the anode-side of Zener diode, so as to make to be connected to Zener diode each
The potential of component can be maintained under negative electricity level.
Figure 18 schematically shows the example of the image forming apparatus according to the present exemplary embodiment.Except using multiple Zeners
Diode 15f and 15e instead of beyond the Zener diode 15 (that is, voltage maintain element) that is shown in Figure 13, shown in Figure 18
Image forming apparatus are similar with the image forming apparatus described in the second exemplary embodiment.Therefore, identical reference refers to
Show similar component.
In the present example embodiment, (that is, the voltage of the Zener voltage with 200 [V] maintains unit to Zener diode 15e
Part 15) anode-side ground connection.In addition, the cathode side of Zener diode 15e is connected to the cathode side of Zener diode 15f, and
The anode-side of Zener diode 15f is connected to secondary transfer printing to edger roll 13 and driven roller 11.Zener diode 15f has 400 [V]
Zener voltage.When the first Zener diode refers to Zener diode 15e and the second Zener diode refers to Zener two
During pole pipe 15f, the first and second Zener diodes are reversed connection.In addition, when the first predetermined potential refers to Zener diode
The Zener voltage 200 [V] of 15e and when the second predetermined potential refers to Zener voltage 400 [V] of Zener diode 15f, first
Absolute value with the second predetermined potential is different from each other.
In the present example embodiment, the potential of intermediate transfer belt 10 is maintained at negative value, as described below.For example,
By promoting negative electricity toner-particle to adhere to intermediate transfer belt 10 centre is cleaned to move to corresponding photosensitive drums 1a to 1d
In the case of transfer belt 10, it is necessary to which intermediate transfer belt 10 is maintained into negative potential.
When negative voltage (- 1000 [V]) is applied to secondary transfer roller 20 by secondary transfer printing power supply 21, electric current is neat from ground connection
The diode 15e that receives flows to secondary transfer roller 20 via intermediate transfer belt 10 and secondary transfer printing to edger roll 13.This moment, because electric current from
Cathode side flows to anode-side, so the voltage of opposite polarity is applied to Zener diode 15f.Because the moon of Zener diode 15f
Pole side is grounded via Zener diode 15e, so the anode-side of Zener diode 15f can maintain Zener voltage.Therefore, two
Secondary transfer is to the potential of edger roll 13, driven roller 11 and metallic roll 23a, 23b, 23c and 23d because these components are connected to Zener two
The anode-side of pole pipe 15f and can maintain under -400 [V].
Regardless of the polarity of the voltage for being applied, if the potential of intermediate transfer belt 10 can be in first transfer surface
Maintained at upstream side and downstream under essentially identical level, then can prevent the potential of intermediate transfer belt along whole first
Transfer surface changes and maintains under desired potential (- 400 [V]) potential of each first transfer section.By at the beginning of each
The potential of secondary transfer section maintains desired negative potential, it is ensured that the negative electricity toner-particle for adhering to intermediate transfer belt 10 can
To move to corresponding photosensitive drums 1a to 1d.
Image forming apparatus according to the present exemplary embodiment are using multiple Zener diodes, each described Zener diode
Being used as voltage maintains element, the multiple Zener diode to be connected in series.The reason for below illustrating above-mentioned construction.
Figure 19 shows the relation between secondary transfer printing voltage and intermediate transfer belt potential.In Figure 19, what abscissa referred to
It is secondary transfer printing voltage [V], and ordinate is referred to [V] with voltage.For evaluating between secondary transfer printing voltage and band potential
Relation voltage maintain element example be with larger resistance value (for example, resistive element of 100 [M Ω]) resistance unit
Part, rheostat (there is the varistor voltage of 200 [V]) and Zener diode.
Such as understand from Figure 19, in the case where rheostat is used as voltage maintenance element, no matter the polarity of secondary transfer printing voltage
How, the absolute value with potential is all maintained under essentially identical level (that is, varistor voltage).If more specifically, applied
Voltage to rheostatic two ends exceedes varistor voltage, then electric current flows through suddenly rheostat, and rheostatic two
End maintains varistor voltage.In the case where resistive element is used as voltage maintenance element, band potential is with secondary transfer printing electricity
Pressure increases and is becoming proportionately larger.
Such as understand from Figure 19, if rheostat is used as voltage and maintains element, regardless of the polarity of secondary transfer printing voltage,
Absolute value with potential is all uniquely fixed on predeterminated level (varistor voltage).Therefore, in positive polarity and negative polarity
Each, it is difficult to independently optimization band potential value.If for example, needed the electricity of each first transfer section for first transfer
Gesture is set to 200 [V], or if necessary to the potential of each first transfer section is maintained under -400 [V] so that negative electricity is mixed colours
Agent particle moves to each photosensitive drums from intermediate transfer belt 10, then these requirements can not meet.
If the resistive element of end ground connection is used as voltage and maintains element, positive electricity (or negative electricity) band potential with it is secondary
Transfer voltage proportionally increases (or reduction).The desired value of secondary transfer printing voltage according to various conditions (for example, recording materials and
Environment) and significantly change.On the other hand, for first transfer section office first transfer potential desired value according to above-mentioned
Condition and change not so much.It is therefore often difficult to suitably setting secondary transfer printing voltage and for the first time transfer both potentials.
If on the contrary, Zener diode be used as voltage maintain element, with potential in positive polarity and negative polarity
Each can maintain predetermined Zener voltage, and the potential for suppressing intermediate transfer belt simultaneously becomes along whole first transfer surface
Change.Therefore, at the beginning of image forming apparatus are configured to form each by promoting electric current to flow to intermediate transfer belt from power supply component
In the case of the potential of secondary transfer section, the potential of each first transfer section can be prevented in response to being applied just by power supply
Voltage or negative voltage and change, and the desired first transfer electricity for each first transfer section can be separately formed
Gesture.
In addition, it is only one Zener diode 15e that the voltage for being used in the present example embodiment maintains element, its is defeated
Go out positive Zener voltage.However, can be using other constructions.For example, it is three for being connected in series that the voltage shown in Figure 20 maintains element
The combination of individual Zener diode.More specifically, the cathode side ground connection of Zener diode 15f.The anode-side of Zener diode 15f connects
It is connected to the anode-side of Zener diode 15e.The cathode side of Zener diode 15e is connected to metallic roll 23a and is connected to Zener
The anode-side of diode 15g.In addition, the cathode side of Zener diode 15g be connected to secondary transfer printing to edger roll 13, metallic roll 23b,
23c and 23d and driven roller 11.
Used as a set of Zener diode for being interoperatively used as constant voltage elements, Zener diode 15e has 200 [V's]
Zener voltage, Zener diode 15f has the Zener voltage of 400 [V], and Zener diode 15g has the Zener electricity of 50 [V]
Pressure.
When positive voltage is applied to secondary transfer roller 20 by transfer power supply 21, constant current is from secondary transfer roller 20 in
Between transfer belt 10 and secondary transfer printing Zener diode 15g and Zener diode 15e is flowed to edger roll 13.In this case, accordingly
Zener diode can maintain their Zener voltage.The metallic roll 23a for being connected to the cathode side of Zener diode 15e can be with
Maintain under 200 [V].Other metallic rolls 23b, 23c and 23d are connected to the cathode side of Zener diode 15g.Therefore, it can dimension
Hold the voltage of 250 [V], the voltage be Zener diode 15e Zener voltage and Zener diode 15g Zener voltage it is total
With.
In addition, when negative voltage is applied to secondary transfer roller 20, corresponding metallic roll 23a, 23b, 23c and 23d can be tieed up
Hold under -400 [V].For example, as other adoptable constructions, it might be useful to which second, third and the 4th image are formed into station
First transfer potential is set higher than the first image and forms the first transfer potential at station to improve the second to the 4th image formation station
Transferring properties.
In addition, it might be useful to change the quantity of Zener diode to be connected and change for second, third and the 4th
Image forms the first transfer potential of each in station.In addition, when negative voltage is applied, in order to change the first transfer at each station
Potential, it might be useful to increase the quantity of the Zener diode of its anode-side ground connection.
It is secondary transfer printing to be used for the power supply component that electric current is supplied to intermediate transfer belt 10 in the first exemplary embodiment
Roller 20.However, in the 4th exemplary embodiment, power supply component is not limited to secondary transfer roller 20.According to the 4th exemplary implementation
The image forming apparatus of example include to be supplied to electric current the extra conductive member of intermediate transfer belt 10.
More specifically, conductive member usable in the present example embodiment is a pair of charging members 18 and 17, they
The toner-particle remained on intermediate transfer belt 10 can be cleaned.Image forming apparatus according to the 4th exemplary embodiment
The remainder of construction is similar with those of the image forming apparatus described in the first exemplary embodiment.Therefore, identical is attached
Icon note indicates similar component.
Figure 21 is the sectional view for schematically showing the image forming apparatus according to the present exemplary embodiment.It is exemplary according to this
The image forming apparatus of embodiment are with the difference of the image forming apparatus according to the first exemplary embodiment, with conduction
Brush member 18 and charging roller component 17 (that is, charging member) replace cleaning unit 16, the conductive brush member 18 and charging roller structure
Part 17 collects the toner-particle remained on intermediate transfer belt 10.
Remain in the secondary transfer printing toner-particle on intermediate transfer belt 10 and pass through conductive brush member 18 and charging roller component
17 (that is, charging members) charge.Conductive brush member 18 is made up of conductive fiber 18a.Brush charge power supply 60 applies predetermined voltage
Charged with to secondary transfer printing residual toner particle to conductive brush member 18.In the present example embodiment, it is contained in development single
The normal charging polarity of the toner-particle in unit is negative polarity.Therefore, brush charge power supply 60 (that is, the first charge power supply) will just
Voltage is applied to conductive brush member 18, so that the toner-particle for making residual has positive polarity.
Conductive rollers 17 are resilient rollers, and it is included as the polyurethane rubber of main component, the polyurethane rubber has 1 ×
109The specific insulation of Ω cm.Conductive rollers 17 are relative to edger roll 13 with secondary transfer printing via intermediate transfer belt 10, and simultaneously
The gross pressure of 9.8N is given by spring (not shown).Conductive rollers 17 be intermediately transferred band 10 drive so that conductive rollers 17 around
Its pivot center is rotated with the gait of march identical peripheral speed with intermediate transfer belt 10.(that is, second fills roller charge power supply 70
Power supply) voltage of+1500 [V] is applied to conductive rollers 17, to make secondary transfer printing residual toner particle that there is positive polarity.
Conductive brush member 18 is made up of conductive fiber.Brush charge power supply 60 by predetermined voltage be applied to conductive brush member 18 with
Secondary transfer printing residual toner particle is charged.Constituting the conductive fiber 18a of conductive brush member 18 includes nylon component and has
There is 100kF/ square inches of density.Conductive fiber 18a includes carbonaceous conductive agent additive.The per unit length of conductive fiber 18a
Resistance value be 1 × 108Ω/cm.The fineness of conductive fiber 18a is 300T/60F.
The method for cleaning the intermediate transfer belt 10 that can be applied to above-mentioned construction is explained referring to Figure 22.
In the present example embodiment, as described above, when toner-particle is charged by developing cell 4a to 4d, mixing colours
Agent particle has negative polarity.Toner-particle is developed and in corresponding first transfer section by corresponding photosensitive drums 1a to 1d
Place is transferred to intermediate transfer belt 10 for the first time.Then, positive voltage is applied to the state of secondary transfer roller 20 in transfer power supply 21
Under, toner-particle is transferred secondarily to recording materials P (for example, paper) to form image on the recording materialp.
As shown in Figure 22, due to being applied to the influence of the positive voltage of secondary transfer roller 20, intermediate transfer belt 10 is remained in
On be intended to positive polarity without being secondarily transferred to the toner-particle of recording materials P.As a result, the remaining toning of secondary transfer printing
Agent particle is the mixture of positive polarity toner-particle and negative polarity toner-particle.Further, since the surface on recording materials P
The influence of fluctuating, secondary transfer printing residual toner particle is formed locally multiple layers (referring in Figure 22 on intermediate transfer belt 10
Region " A ").
Conductive brush member 18 is positioned on upstream side of the conductive rollers 17 along the direction of motion of intermediate transfer belt 10.Conduction brush
Component 18 is arranged stationarily into relative to the intermediate transfer belt 10 of motion and causes that the distal part of conductive fiber 18a contacts middle
Transfer belt 10.Conductive brush member 18 do not cause any rotation when intermediate transfer belt 10 is moved in the case of by apparatus body component
Support.Therefore, when secondary transfer printing residual toner particle is passed through by filling that conductive brush member 18 and intermediate transfer belt 10 are formed
During electric part, conductive brush member 18 is mechanically scraped the multilayer toner-particle on intermediate transfer belt 10 using difference
Into individual layer (referring to the region " B " in Figure 22).
In addition, because brush charge power supply 60 performs current constant control for positive voltage is applied into conductive brush member 18, institute
With when toner-particle passes through live part, the polarity of secondary transfer printing residual toner particle be changed to positive polarity (with it is aobvious
Toner opposite polarity in shadow treatment).The toner-particle of negative polarity is constantly maintained to be collected by conductive brush member 18.
Then, the secondary transfer printing residual toner particle of conductive brush member 18 is had already passed through along the fortune of intermediate transfer belt 10
Move and reach conductive roller component 17 in dynamic direction.Roller charge power supply 70 by positive voltage (i.e., in the present example embodiment ,+
1500V) it is applied to conductive roller component 17.Therefore, when secondary transfer printing residual toner particle passes through conductive roller component 17 (referring to figure
Region " C " in 22) when, secondary transfer printing residual toner particle is further charged after conductive brush member 18 is had already passed through
To strengthen positive polarity.
Then, the fully charged, toner-particle remained on intermediate transfer belt 10 is moved in first transfer section office
To electronegative photosensitive drums 1a.Then, the toner-particle of photosensitive drums 1a is transferred to by the cleaning that is arranged near photosensitive drums 1a
Unit 5a is collected.
Timing when the toner-particle of positively charged moves to photosensitive drums 1a from intermediate transfer belt 10 and when toner figure
Timing during as being transferred to intermediate transfer belt 10 for the first time from photosensitive drums 1a can be identical or independent of each other.
In the present example embodiment, conductive roller component 17 is positioned at fortune of the conductive brush member 18 along intermediate transfer belt 10
On the downstream in dynamic direction.The arrangement is for making the charge volume of toner-particle when toner-particle has already passed through live part
Unification is effective.Therefore, or even when conductive roller component 17 is not provided with, if the charge volume of toner-particle is in predetermined model
In enclosing, then secondary transfer printing residual toner particle can also be charged using only conductive brush member 18.
As described above, the image forming apparatus according to the present exemplary embodiment including secondary transfer roller 20 except (that is, powering
Component) beyond, also including conductive brush member 18 and charging roller 17 (that is, charging member).Below explanation uses the original of above-mentioned construction
Cause.
Secondary transfer roller 20 described in the first exemplary embodiment has the effect that.First effect is supplied with being enough to
Obtain the secondary transfer current of the amount of gratifying secondary transfer printing characteristic.Second effect is will in each first transfer section office
The first Transfer current of the amount of the potential for being enough to maintain intermediate transfer belt 10 is supplied to each photosensitive drums 1.Therefore, in the first example
Property embodiment described in secondary transfer roller 20 to need operation be power supply component, secondary transfer printing that it can supply desired amount electricity
The first Transfer current of stream and desired amount.
Hereinafter illustrate the relation between the secondary transfer current of desired amount and the first Transfer current of desired amount.It is useful
Be that secondary transfer current is set to the secondary transfer section office that can optimize and recording materials P is transferred in toner image
The current value of transfer efficiency.Figure 23 illustrates the secondary transfer current transformation in the present exemplary embodiment.
Figure 23 is the chart for showing the relation between Transfer current and secondary transfer printing efficiency, and ordinate refers in the chart
It is transfer efficiency, i.e. transmit the secondary transfer printing remnants that reflection densitometer (being provided by Gretagmacbeth) is measured with Macbeth
The measurement result of density.It should be understood that when ordinate value reduces, transfer efficiency is uprised.Recording materials P used in measurement is
Business4200 there is provided by Xerox, entitled is (per Gram Mass：75g/m2) brand-new paper.It should be understood that from figure
Result shown in 23, it is known that because transfer efficiency can be maximized, for the present exemplary embodiment in secondary turn
The optimal magnitude of current of print is 10 μ A.
Next, the following first Transfer current for illustrating the desired amount for the first transfer potential of stabilization.Figure 24 shows
Element (Zener diode) 15 is maintained to be connected to state of the secondary transfer printing to edger roll 13, driven roller 11 and metallic roll 14 in voltage
Under, the measurement result of the potential of the intermediate transfer belt 10 obtained when electric current is supplied from secondary transfer roller 20.In fig. 24, indulge and sit
Mark refers to the potential in the region of each component contact intermediate transfer belt of voltage maintenance element is connected to, and abscissa
Refer to current value.
In fig. 24, dotted line indicates to realize making the first current value for transferring satisfied potential.If current value exceedes
Level as required for dotted line is indicated, then can form enough potentials in each first transfer section office.It should be understood that from figure
Result shown in 24 is, it is known that in the present example embodiment for maintaining for secondary turn required for the first potential for transferring
Print electric current is greater than or equal to 20 μ A's.If it is assumed that the electric current from the supply of secondary transfer roller 20 is uniform via intermediate transfer belt 10
Ground is flowed into the first transfer section that each image forms station, then the electric current for being assigned to the photosensitive drums 1 that each image forms station is 5
μA.Excessive electric current is flowed into Zener diode 15.
Therefore, the magnitude of current and TB of first transfer satisfaction is made to represent the electric current for being supplied to intermediate transfer belt 10 when TA is represented
During amount, desired first transfer performance can be realized when TB is more than or equal to TA.
If the device of supply magnitude of current TB is limited to secondary transfer roller, required delivery is more than or equal to 20 μ A
(its magnitude of current (10 μ A) for being more than optimization secondary transfer printing performance).Therefore, as described in the first exemplary embodiment, if only
Secondary transfer roller supplies electric current, then need to increase delivery in for the acceptable scope of secondary transfer printing performance, so as to obtain
Desired first transfer performance.
In view of the above, the image forming apparatus according to the present exemplary embodiment are using charging member 18 and 17 as confession
Electric components.Thus, can be optimised for desired secondary transfer current amount from the magnitude of current of the supply of secondary transfer roller 20, and
And may insure gratifying first transferring properties.
More specifically, the pilot brush charge power supply 60 of controller 100 and roller charge power supply 70 with by electric current via conduction brush structure
Part 18 and conductive rollers 17 are supplied to intermediate transfer belt 10.
It is 20 μ A as described previously for the magnitude of current required for first transfer.Therefore, if conductive brush member 18, conduction
The total current of roller 17 and secondary transfer roller 20 is more than or equal to 20 μ A, then can maintain the enough potentials for first transfer.
Therefore, though when the electric current supplied from secondary transfer roller 20 is 10 μ A, if from charging member 18 and 17 supply electric current it is big
In or equal to 10 μ A, then total current can also become greater than or equal to 20 μ A.Therefore, it can be appropriately performed secondary transfer printing and first
Both transfers.
Timing is applied according to the transfer process voltage of the present exemplary embodiment referring to Figure 25 explanations.Figure 25 be show it is suitable
The time diagram of the image forming operation of sequence, the image forming operation of the order includes：First turning is performed after a start operation
Print treatment and secondary transfer printing treatment；And, stop main motor after two recording materials P are exported.
If main motor response starts operation in the instruction of image forming operation, under timing S1, controller 100 is controlled
Each power supply prevents toner-particle from conduction so that toner holding electric current is supplied into conductive brush member 18 and conductive rollers 17
Brush member 18 and conductive rollers 17 drop.This moment, equal to the charging current of the total current for flowing through conductive brush member 18 and conductive rollers 17
Value (that is, toner keeps current value) is set as 5 μ A.Hereafter, flowed from charging member (that is, conductive brush member 18 and conductive rollers 17)
Electric current to intermediate transfer belt 10 is referred to as charging current.
Start for image formed first transfer process before, controller 100 promote secondary transfer roller 20 start by
Electric current is supplied to intermediate transfer belt 10 (in this case, from electric current hereinafter referred to as " the secondary transfer printing electricity of the supply of secondary transfer roller 20
Stream ").Simultaneously (under timing S2), controller 100 increase charging current so that conduction brush 18 and conductive rollers 17 by electric current (i.e., just
Secondary transfer compensation electric current) it is supplied to intermediate transfer belt 10.In the present example embodiment, secondary transfer current value is 10 μ A, and
And first transfer compensation current is 15 μ A, but current setting value is also not necessarily limited to above-mentioned example.For example, what ought be performed at present turns
When print treatment is only first transfer process, it might be useful to which only secondary transfer roller 20 supplies required electric current.
Under timing S3, controller 100 starts first transfer in the state of scheduled current is supplied to intermediate transfer belt 10
Treatment, to allow toner image to be transferred to intermediate transfer belt 10 in succession from corresponding photosensitive drums 1.If first
The secondary toner image for being transferred to intermediate transfer belt 10 reaches secondary transfer printing part, then controller 100 changes over charging current
For the secondary transfer printing desired current value for the treatment of.More specifically, under timing S4, controller 100 increases to charging current
Toner charging current value (that is, 20 μ A), and perform current constant control to be fixed on the secondary transfer current value of 10 μ A simultaneously.At this
In exemplary embodiment, it has been that secondary transfer printing processes the value (10 μ A) for optimizing that secondary transfer current has.Therefore, when image shape
When forming apparatus perform first transfer process and secondary transfer printing treatment, optimal electric current can be continually provided.
Then, under timing S5, image forming apparatus are proceeding to terminate first transfer while secondary transfer printing is processed
Treatment.If image forming apparatus terminate secondary transfer printing treatment, under timing S6, controller 100 stops supplying secondary transfer
Electric current.
Then, controller 100 will flow through conduction brush 18 and the total current of conductive rollers 17 maintains 20 μ A with to toner
Grain charges, until the rear end of secondary transfer printing residual toner particle (that is, the toner-particle for being produced in secondary transfer printing treatment)
Untill portion passes through conduction brush 18 and conductive rollers 17 (referring to timing S7).After timing S7, controller 100 can change charging current
Change to toner and keep current value.If the cleaning of intermediate transfer belt 10 terminates, under timing S8, controller 100 stops will
Voltage is applied to the image forming operation of conduction brush 18 and conductive rollers 17 and termination order.
As described above, being performed at timing in secondary transfer printing, have for secondary turn from the electric current of the supply of secondary transfer roller 20
The optimal magnitude of current (10 μ A) of print treatment.Charging member 18 and 17 supplies extra charging current to meet at first transfer
The magnitude of current required for reason.Therefore, the image forming apparatus according to the present exemplary embodiment can improve secondary transfer printing performance
While be appropriately performed first transfer process.
Although the power supply component for being used in the present example embodiment is charging member 18 and 17, but it is also possible to use it
Its component.For example, the cleaning doctor of the cleaning unit 16 described in the first exemplary embodiment can be used as conductive member.More
Body ground, it might be useful to a kind of device for applying a voltage to cleaning doctor is provided, to make cleaning doctor can serve as leading
Electric components.
Above-mentioned charging current is not limited to flow through the total current of conductive brush member 18 and conductive roller component 17.If for example, saved
Conductive roller component 17 is omitted, then the only conductive supplying charging current of brush member 18.
In addition, above-mentioned arrangement can be applied to the construction shown in the second exemplary embodiment, it is provided with needing and each
The relative component of first transfer section.For example, as shown in Figure 26, or even when exemplary second with the conductive replacement of brush member 18
In embodiment during cleaning unit 16 described in reference picture 17, it is also possible to obtain similar effect.
In addition, when intermediate transfer belt 10 has the resistance value in relatively low circumferentially direction, charging current can increase
Amount to be supplied to the electric current of intermediate transfer belt 10 and the electric current flowed into first transfer section can be increased.If do not increased
The magnitude of current increased in the case of big secondary transfer current amount to be supplied to each first transfer section is feasible, then can obtain
The effect that must prevent the potential of each first transfer section from changing in image forming operation.
Figure 27 schematically shows another image forming apparatus according to the present exemplary embodiment, and described image is formed and set
It is standby to include：Multiple images carrier, each described image carrier delivers toner image；Turn in the middle of movable conductive annular
Print band, it can be first transferred with toner image from multiple images carrier；With multiple tensioning member, it is interoperatively tensioned
Intermediate transfer belt.Image forming apparatus shown in Figure 27 also include secondary transfer printing component, and it is formed together with intermediate transfer belt
Secondary transfer printing part is secondarily transferred to recording materials with by the toner image from intermediate transfer belt；Transfer power supply, it will foot
Enough voltage is applied to secondary transfer printing component；Voltage maintains element, and it is connected to multiple tensioning member；And conductive member, it connects
Touch intermediate transfer belt and be supplied to intermediate transfer belt with by electric current.
Image forming apparatus shown in Figure 27 are with the similar part of the equipment shown in Figure 21, Zener diode 15
(that is, voltage maintains element) is connected to two tensioning member (that is, secondary transfer printings pair for interoperatively forming first transfer surface
Edger roll 13 and driven roller 11), and image forming apparatus shown in Figure 27 exist with the difference of the equipment shown in Figure 21
In being not provided with metallic roll 14 (that is, contact member).Increase is configured to shown in Figure 27 and flows into each first transfer section
In electric current because (that is, first transfer table can interoperatively be formed to edger roll 13 and driven roller 11 in secondary transfer printing
The component in face) maintain in the state of predetermined potential or the potential higher than the predetermined potential from addition to secondary transfer roller 20
Component extraly supply electric current.Construction shown in Figure 27 can be without increase from the electric current of the supply of secondary transfer roller 20
In the case of increase flow into each first transfer section in electric current.In addition, as shown in Figure 28, auxiliary is connected in cleaning doctor
In the case of power supply 80, charging member 18 and 17 can be replaced with cleaning unit 16.Image forming apparatus shown in Figure 28 can
Obtain the effect similar with image forming apparatus shown in figure 27.
Although illustrating the present invention with reference to exemplary embodiment, it should be understood that the present invention is not by disclosed exemplary reality
Apply example limitation.The scope of following claims will be consistent with broadest interpretation, so as to comprising all modifications, equivalent structure and
Function.
Claims (15)
1. a kind of image forming apparatus, it includes：
Image-carrier, it is configured to carry toner image；
Conductive intermediate transfer belt, it can be moved in an annular manner, and toner image is transferred to centre for the first time from image-carrier
Transfer belt；
First tensioning member and the second tensioning member, it is configured to be tensioned intermediate transfer belt；
Power supply component, its contact intermediate transfer belt, and be configured to for electric current to be supplied to intermediate transfer belt；
Contact member, its contact intermediate transfer belt；With
Voltage maintains element, and it is connected to contact member and is connected to one of the first tensioning member and the second tensioning member,
Wherein, relative to the direction of motion of intermediate transfer belt, image-carrier is between the first tensioning member and the second tensioning member
Contact intermediate transfer belt,
Contact member is arranged on the intermediate transfer belt side that imaging support is arranged, and relative to the motion side of intermediate transfer belt
To, contact member contacts intermediate transfer belt between the first tensioning member and the second tensioning member, and
According to the electric current of intermediate transfer belt is flowed to from power supply component, contact member and maintain that element is connected with voltage the are kept
First, the potential of at least one second tensioning member is more than or equal to predetermined potential.
2. image forming apparatus according to claim 1, wherein, relative to the direction of motion of intermediate transfer belt, image is carried
Body is arranged on the downstream of the first tensioning member and the upstream side of second component.
3. image forming apparatus according to claim 2, wherein,
Voltage maintains element to be connected to the first tensioning member, and
Relative to the direction of motion of intermediate transfer belt, contact member is in the downstream of image-carrier and the upstream side joint of second component
Touch intermediate transfer belt.
4. image forming apparatus according to claim 3, wherein, contact member contacts the inner peripheral surface of intermediate transfer belt.
5. image forming apparatus according to claim 4, wherein, power supply component contacts the outer peripheral face of intermediate transfer belt.
6. image forming apparatus according to claim 5, also include：
Power supply, it is configured to apply a voltage to power supply component,
Wherein, electric current is supplied to intermediate transfer belt from power supply via power supply component.
7. image forming apparatus according to claim 6, also include：
Charging member, it is arranged at the position relative with the first tensioning member via intermediate transfer belt, and be configured to it is right
The toner adhered on intermediate transfer band charges；With
Charge power supply, it is configured to apply a voltage to charging member,
Wherein, toner image be transferred to for the first time from image-carrier intermediate transfer belt and then toner image at secondary turn
When being secondarily transferred to recording materials from intermediate transfer belt at print part, supplied via intermediate transfer belt according to from secondary transfer printing component
Electric current be added via the electric current that intermediate transfer belt is supplied with from charging member obtained by electric current sum, keep the first tensioning member
Potential and contact member potential be more than or equal to predetermined potential.
8. image forming apparatus according to claim 6, also include：
Control unit, it is configured to control the power supply and the charge power supply,
Wherein, the current control that control unit will be supplied to intermediate transfer belt from power supply component is constant current amount, and
Control unit will be supplied to the current control of intermediate transfer belt into the time that treatment is formed according to image from charging member
Change.
9. image forming apparatus according to claim 8, wherein, control unit is performed control to just will be supplied from charging member
The magnitude of current for being given to intermediate transfer belt is controlled into more than the magnitude of current that intermediate transfer belt is supplied to from power supply component.
10. image forming apparatus according to any one of claim 1 to 9, wherein, there is multiple images carrier, each figure
Image carrier carries the toner image of different colours.
11. image forming apparatus according to claim 10, wherein, there are multiple contact members, each contact member arrangement
Into corresponding with each image-carrier.
12. image forming apparatus according to claim 11, wherein,
The multiple contact member is multiple metallic rolls, and
Along the direction of motion of intermediate transfer belt, the multiple metallic roll is arranged on right each other by image-carrier and intermediate transfer belt
The downstream of the first transfer section that should be formed.
13. image forming apparatus according to claim 12, also include：
Exposing unit, it is configured to expose the multiple image-carrier respectively,
Wherein, in the case that exposing unit forms electrostatic latent image on image-carrier, exposing unit also exposes each image load
The non-image portion for not forming image of body.
14. image forming apparatus according to claim 10, wherein, voltage maintains the element that element is voltage constant.
15. image forming apparatus according to claim 14, wherein,
It is multiple Zener diodes that voltage maintains element, and
Positive current or negative current can be supplied to intermediate transfer belt by power supply component, and at least one Zener diode reversely connects
It is connected to another Zener diode.
Applications Claiming Priority (9)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP2012-085028 | 2012-04-03 | ||
| JP2012-085027 | 2012-04-03 | ||
| JP2012085027 | 2012-04-03 | ||
| JP2012085028 | 2012-04-03 | ||
| JP2012085548 | 2012-04-04 | ||
| JP2012-085548 | 2012-04-04 | ||
| JP2013023425A JP5855033B2 (en) | 2012-04-03 | 2013-02-08 | Image forming apparatus |
| JP2013-023425 | 2013-02-08 | ||
| CN201310105943.6A CN103365173B (en) | 2012-04-03 | 2013-03-29 | Image forming apparatus |
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| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CN201310105943.6A Division CN103365173B (en) | 2012-04-03 | 2013-03-29 | Image forming apparatus |
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| CN106873332A true CN106873332A (en) | 2017-06-20 |
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| CN201310105943.6A Active CN103365173B (en) | 2012-04-03 | 2013-03-29 | Image forming apparatus |
| CN201710105753.2A Pending CN106873332A (en) | 2012-04-03 | 2013-03-29 | Image forming apparatus |
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| CN201310105943.6A Active CN103365173B (en) | 2012-04-03 | 2013-03-29 | Image forming apparatus |
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| EP (1) | EP2648050B1 (en) |
| JP (1) | JP5855033B2 (en) |
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| PH (1) | PH12013000096A1 (en) |
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Families Citing this family (22)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JP6141057B2 (en) * | 2012-04-03 | 2017-06-07 | キヤノン株式会社 | Image forming apparatus |
| JP5911357B2 (en) * | 2012-04-03 | 2016-04-27 | キヤノン株式会社 | Image forming apparatus |
| JP5855033B2 (en) * | 2012-04-03 | 2016-02-09 | キヤノン株式会社 | Image forming apparatus |
| JP6157179B2 (en) * | 2012-04-04 | 2017-07-05 | キヤノン株式会社 | Image forming apparatus |
| JP6271845B2 (en) * | 2012-04-04 | 2018-01-31 | キヤノン株式会社 | Image forming apparatus and intermediate transfer unit |
| JP5942905B2 (en) * | 2013-03-21 | 2016-06-29 | コニカミノルタ株式会社 | Image forming apparatus and control method thereof |
| JP6188449B2 (en) * | 2013-06-26 | 2017-08-30 | キヤノン株式会社 | Image forming apparatus |
| JP6271936B2 (en) * | 2013-10-08 | 2018-01-31 | キヤノン株式会社 | Image forming apparatus |
| JP6261335B2 (en) * | 2013-12-27 | 2018-01-17 | キヤノン株式会社 | Image forming apparatus |
| JP2015200711A (en) * | 2014-04-04 | 2015-11-12 | キヤノン株式会社 | image forming apparatus |
| JP6395499B2 (en) * | 2014-08-14 | 2018-09-26 | キヤノン株式会社 | Image forming apparatus |
| WO2016088197A1 (en) | 2014-12-02 | 2016-06-09 | キヤノン株式会社 | Image forming device |
| JP6053976B2 (en) * | 2016-03-23 | 2016-12-27 | キヤノン株式会社 | Image forming apparatus |
| JP6818448B2 (en) * | 2016-06-29 | 2021-01-20 | キヤノン株式会社 | Image forming device |
| CN107664940B (en) * | 2016-07-29 | 2020-08-25 | 佳能株式会社 | Image forming apparatus with a toner supply device |
| JP6821355B2 (en) * | 2016-08-04 | 2021-01-27 | キヤノン株式会社 | Image forming device |
| JP6214747B2 (en) * | 2016-12-01 | 2017-10-18 | キヤノン株式会社 | Image forming apparatus |
| JP2018105921A (en) | 2016-12-22 | 2018-07-05 | キヤノン株式会社 | Image formation apparatus |
| JP6849466B2 (en) * | 2017-02-09 | 2021-03-24 | キヤノン株式会社 | Image forming device |
| JP6942599B2 (en) * | 2017-10-13 | 2021-09-29 | キヤノン株式会社 | Image forming device |
| JP7423283B2 (en) | 2019-12-02 | 2024-01-29 | キヤノン株式会社 | Image forming device |
| EP3974839B1 (en) * | 2020-09-23 | 2024-03-27 | Roche Diagnostics GmbH | A method for detecting and reporting an operation error in an in-vitro diagnostic system, a transport device for a laboratory sample distribution system, and a laboratory sample distribution system |
Family Cites Families (32)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JPH03186876A (en) | 1989-12-16 | 1991-08-14 | Canon Inc | Image forming device |
| JP3245240B2 (en) | 1992-01-22 | 2002-01-07 | 株式会社リコー | Transfer device for image forming device |
| JP3434071B2 (en) * | 1994-12-28 | 2003-08-04 | 株式会社リコー | Transfer device for image forming device |
| JP3416389B2 (en) | 1996-04-26 | 2003-06-16 | キヤノン株式会社 | Image forming device |
| JP3462739B2 (en) * | 1997-12-24 | 2003-11-05 | シャープ株式会社 | Color image forming equipment |
| JP2001175092A (en) * | 1999-12-21 | 2001-06-29 | Canon Inc | Image forming device |
| JP2001183916A (en) * | 1999-12-24 | 2001-07-06 | Canon Inc | Image forming device |
| JP3820840B2 (en) * | 2000-03-14 | 2006-09-13 | コニカミノルタビジネステクノロジーズ株式会社 | Image forming apparatus |
| JP2001265135A (en) * | 2000-03-14 | 2001-09-28 | Canon Inc | Image forming device |
| JP2002040749A (en) * | 2000-07-19 | 2002-02-06 | Canon Inc | Image forming device |
| EP1351101B1 (en) * | 2001-01-12 | 2012-11-21 | Fuji Xerox Co., Ltd. | Image forming device |
| JP3583379B2 (en) | 2001-04-18 | 2004-11-04 | 松下電器産業株式会社 | Color image recording device |
| JP4004020B2 (en) | 2001-07-23 | 2007-11-07 | 株式会社リコー | Bias application method, bias application device, and image forming apparatus |
| JP4461653B2 (en) * | 2001-08-20 | 2010-05-12 | コニカミノルタビジネステクノロジーズ株式会社 | Image forming apparatus |
| KR100408295B1 (en) | 2001-09-06 | 2003-12-01 | 삼성전자주식회사 | Cleaning device of liquid electrophotographic printer |
| JP3697193B2 (en) * | 2001-10-16 | 2005-09-21 | キヤノン株式会社 | Image forming apparatus |
| JP2003248383A (en) * | 2002-02-26 | 2003-09-05 | Canon Inc | Image forming apparatus |
| JP2003280331A (en) * | 2002-03-22 | 2003-10-02 | Ricoh Co Ltd | Image forming apparatus |
| KR100497480B1 (en) | 2002-11-19 | 2005-07-01 | 삼성전자주식회사 | Color image forming machine |
| JP2005250254A (en) * | 2004-03-05 | 2005-09-15 | Canon Inc | Image forming apparatus |
| US7289757B2 (en) * | 2004-03-26 | 2007-10-30 | Lexmark International, Inc. | Shared high voltage power supply for image transfer in an image forming device |
| JP2006221048A (en) * | 2005-02-14 | 2006-08-24 | Canon Inc | Image forming apparatus |
| JP4496111B2 (en) | 2005-03-14 | 2010-07-07 | 株式会社リコー | Unit and image forming apparatus |
| JP2006259639A (en) * | 2005-03-18 | 2006-09-28 | Ricoh Co Ltd | Image forming apparatus |
| JP2006259640A (en) * | 2005-03-18 | 2006-09-28 | Ricoh Co Ltd | Image forming apparatus |
| JP4372716B2 (en) | 2005-04-27 | 2009-11-25 | シャープ株式会社 | Transfer device and image forming apparatus |
| JP2009075357A (en) * | 2007-09-20 | 2009-04-09 | Oki Data Corp | Image forming apparatus |
| JP5158508B2 (en) | 2008-09-30 | 2013-03-06 | 株式会社リコー | Image forming apparatus |
| JP5267942B2 (en) | 2009-03-17 | 2013-08-21 | 株式会社リコー | Image forming apparatus |
| JP4878635B2 (en) | 2009-08-18 | 2012-02-15 | キヤノン株式会社 | Image forming apparatus |
| JP2011128380A (en) * | 2009-12-17 | 2011-06-30 | Canon Inc | Image forming apparatus |
| JP5855033B2 (en) * | 2012-04-03 | 2016-02-09 | キヤノン株式会社 | Image forming apparatus |
-
2013
- 2013-02-08 JP JP2013023425A patent/JP5855033B2/en active Active
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| JP2013231942A (en) | 2013-11-14 |
| RU2013114875A (en) | 2014-10-10 |
| JP5855033B2 (en) | 2016-02-09 |
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| KR101657550B1 (en) | 2016-09-19 |
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| US20180039210A1 (en) | 2018-02-08 |
| US9158238B2 (en) | 2015-10-13 |
| CN103365173A (en) | 2013-10-23 |
| RU2016116898A (en) | 2016-09-10 |
| US9817342B2 (en) | 2017-11-14 |
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| US20190137910A1 (en) | 2019-05-09 |
| US20160320727A1 (en) | 2016-11-03 |
| KR20130112767A (en) | 2013-10-14 |
| PH12013000096B1 (en) | 2015-04-06 |
| US10180643B2 (en) | 2019-01-15 |
| BR102013007934A2 (en) | 2015-06-16 |
| US10627749B2 (en) | 2020-04-21 |
| PH12013000096A1 (en) | 2015-04-06 |
| EP2648050B1 (en) | 2022-02-02 |
| EP2648050A2 (en) | 2013-10-09 |
| US20150316874A1 (en) | 2015-11-05 |
| KR101802670B1 (en) | 2017-11-28 |
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| CN103365173B (en) | 2017-04-12 |
| EP2648050A3 (en) | 2017-12-13 |
| RU2636267C2 (en) | 2017-11-21 |
| US9417568B2 (en) | 2016-08-16 |
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Application publication date: 20170620 |